The people who watched Dwight Howard dominate the N.B.A. up close don’t need reminders of how great he once was.

They remember when he and LeBron James were the best players in the league. They remember what made Howard a three-time defensive player of the year, an eight-time All-Star and a member of the All-N.B.A. first team five years in a row.

When they saw the N.B.A.’s 75th anniversary list of the best players ever, selected by a panel of media, players and coaches, they realized someone had been forgotten: Howard.

“That was kind of crazy,” said Otis Smith, the former Orlando Magic general manager, who built teams around Howard.

Said Stan Van Gundy, who coached him at his peak: “Whatever the reason that he got left out, there’s something more than basketball to it.”

In the decade since Howard dominated the league, he has gone from centerpiece of a finals team to disappointing star to doubted role player. The N.B.A.’s 75 best list, which ended up with 76 players because of a tie, was just one example of how Howard’s once-undeniable impact is now challenged.

Howard is now part of a Lakers team hailed for being filled with players almost certain to make the Hall of Fame. During those conversations, the players cited are usually Anthony Davis, LeBron James, Russell Westbrook and Carmelo Anthony. But Howard’s name is often left out, despite a list of accomplishments few can match. Among this group of Lakers, he plays the least, at around 15 minutes per game, and his legacy is questioned most often.

The man who was once James’s greatest adversary has faded into the background.

“Why do you think people don’t like you?” Charles Barkley, in his role as a TNT analyst, asked Howard during a studio show in 2016.

After a bit of back and forth, Howard answered: “I think I was very likable in Orlando, and the way that situation ended, I think people felt I’m just this bad guy.”

He spent eight seasons with the Magic, who drafted him No. 1 overall out of high school in 2004. Despite his outsize physique, basketball acumen and talent, he faced critiques even then — often about whether he smiled too much.

“Our core group, we understood each other and if it was time to not joke, we would just tell him, ‘Not right now,’ or he could sense it,” said Jameer Nelson, the Magic’s starting point guard while Howard was there. “We were winning so many games during that time it’s almost like, how can you tell somebody not to joke when you’re still winning? You’re still statistically one of the best teams in the league on both ends of the floor.”

Howard led the Magic to the N.B.A. finals in 2009 after beating James’s Cleveland Cavaliers in the Eastern Conference finals. The Magic lost to the Lakers in the N.B.A. finals, and lost in the Eastern Conference finals in 2010.

Then trouble started. There were rumblings Howard wanted out of Orlando. Nelson recalled trade rumors emerging about other players. Sometimes those players wondered if Howard was behind them.

“It was a painful time even coming to work,” Nelson said.

One day, Van Gundy told reporters Howard was trying to oust him, and Howard, not knowing what had just been said, playfully crashed Van Gundy’s news conference with a smile. The awkward moment — Howard with his arm across the shoulders of a soda-sipping Van Gundy — became a meme.

“I’m not trying to run from it,” Van Gundy said in a phone interview recently. “I don’t think the incident that he and I had — we only had one — I don’t think it reflected real well on either one of us.”

The Magic traded Howard to the Lakers before the 2012-13 season. The Phoenix Suns had traded guard Steve Nash to the Lakers a month earlier, and the pair appeared on the cover of Sports Illustrated together with a now-infamous headline: “Now This Is Going to Be Fun.”

Nash, who had won two Most Valuable Player Awards in Phoenix, broke his leg in the second game of the season. Howard struggled through injuries and clashed with Kobe Bryant, the face of the team. The Lakers went 45-37 and Howard was an All-Star again. But after the season ended with a first-round loss in the playoffs, he moved on as a free agent, leaving behind an enraged fan base.

Howard chose Houston, another team that expected him to help it win a championship and that had even staged a special news conference with Hakeem Olajuwon and Yao Ming. But this team, with a talented guard in James Harden, also wouldn’t be built around Howard.

“You could tell it was different for him,” said Corey Brewer, who joined the Rockets in Howard’s second year there.

There were reports of discontent between Howard and Harden.

“They were just different,” Brewer said. “I wouldn’t say it didn’t mesh. Just different personalities. I don’t feel like they had any problems that I knew of. We were trying to win.”

With Howard and Harden, the Rockets made it to the Western Conference finals during the 2014-15 season and lost to Golden State. Critiques of Howard’s game continued; Barkley, for example, said often that Howard never improved his game after his time in Orlando.

All the while, the sport was changing, making traditional centers like Howard less effective. After one more season in Houston, Howard spent the next five years on five teams — the Atlanta Hawks, the Charlotte Hornets, the Washington Wizards, the Lakers and the Philadelphia 76ers. He was also traded to the Grizzlies and the Nets, then waived before playing any games. He returned to the Lakers this season for a third stint.

One evening in Washington, after a game early in his lone season there, an arena worker screamed “Brick!” when Howard missed practice free throws, according to The Washington Post and The Athletic.

Howard didn’t spend much time physically with the Wizards, sidelined for most of the season after back surgery.

He became seen as a player who would be a problem, who would complain about his minutes and opportunities. He was booed in Orlando and booed in Los Angeles.

When the Lakers signed him in 2019, they gave him a non-guaranteed contract, which provided little security for Howard if the reunion went poorly.

“He came in every day, pounded everybody, said hi to everybody, made sure everybody knew he was happy in the situation he was in,” said JaVale McGee, who started ahead of Howard with the Lakers during the 2019-20 season. “He constantly was the ultimate professional.”

McGee added, when asked if showing that quality seemed important to Howard: “I definitely think it was important just because of hearsay and the way people talk about you in the league, especially G.M.s and coaches. It can really mess up your image.”

The Lakers won a championship in 2020 with Howard coming off the bench throughout the playoffs.

“You look at him right now, he’s a sub,” said Smith, Howard’s former general manager. “He comes in, he adds some energy, plays some defense. But if you go back to in his prime when the world revolved around him and teams have to account for him before they account for anything else because he’s such a presence on the inside. Everyone had to adjust for that. The game has changed so much.”

The way the Lakers use their centers reflects that change.

Howard started this season coming off the Lakers’ bench for DeAndre Jordan, who started at center. But Jordan has only played in one game since Christmas. In that span, Howard has played in only five of eight games and averaged 13 minutes per game. Lately, LeBron James has been the Lakers’ starting center.

Perhaps time has dulled his past accomplishments. Perhaps Howard’s complicated journey has affected his legacy.

“I have people ask me like, ‘Oh, do you think he’s a Hall of Famer?’” Van Gundy said. “Do I think he’s a Hall of Famer? Are you kidding me?”

Van Gundy rattled off Howard’s All-N.B.A. and defensive awards.

“Go check and see how many people have done that,” he said.