Welcome to Week 18 of the N.F.L. season, the superfluous coda to an already-grueling marathon that few besides the television networks and advertisers really wanted.

Get ready to discover the answers to some crucial questions this weekend. For example: Will the Dallas Cowboys finish second, third or fourth in the N.F.C. playoff seedings? A second-place finish guarantees them a home playoff game against a wild-card opponent, while third or fourth earns them a home playoff game against a different wild-card opponent. The stakes could hardly be any lower.

The Cowboys (11-5) will face the Philadelphia Eagles (9-7), who have already clinched a wild-card berth and may be missing many of their starters due to a coronavirus outbreak. Also, Saturday night’s contest will not actually determine the Cowboys’ final seeding. To learn their true fate, viewers will have to tune in for such can’t-miss Sunday action as the 12-4 Tampa Bay Buccaneers’ showdown with the 5-11 Carolina Panthers.

Cowboys-Eagles is actually one of Week 18’s most important games, which is why the N.F.L. moved it to a prime time television slot. Most of the weekend’s games have much more esoteric meaning, if they have any at all.

The Green Bay Packers (13-3) have already clinched home-field advantage throughout the N.F.C. playoffs and a coveted first-round bye. All but two of the division titles have been decided. The Arizona Cardinals (11-5) and Los Angeles Rams (12-4) will duke it out for the N.F.C. West championship on Sunday, though not against each other.

The New England Patriots (10-6) can improve their chances to win the A.F.C. East by beating the Miami Dolphins (8-8), who were eliminated from postseason contention last week, while the Buffalo Bills (10-6) can clinch the division by defeating the Jets, who were eliminated in 1972. All four divisional challengers still reach the playoffs if they lose, robbing their games of much of their potential drama.

The only Week 18 game with true playoffs-or-bust stakes for both teams pits the 9-7 Los Angeles Chargers against the 9-7 Las Vegas Raiders. In most weeks, Chargers-Raiders would be pre-empted across much of the East Coast by a Cowboys game, or perhaps a three-hour marathon of Patrick Mahomes’s insurance commercials. On Sunday, it has been moved to prime time and is being hyped as the grand regular-season finale.

The N.F.L. strives annually to create a final-week schedule that begins with an appetizer sampler of lesser matchups but gradually builds to a Sunday night crescendo in which all of the playoff pieces satisfyingly fall together like the resolution of a murder mystery. The league could have accomplished that feat week, when the Eagles, Bills, Tennessee Titans and Cincinnati Bengals all earned playoff berths while the Dolphins, Washington Football Team, Cleveland Browns and other also-rans were mercifully eliminated.

Had the season ended in Week 17, the Cincinnati Bengals’ A.F.C. North-clinching 34-31 upset of Kansas City would likely have been moved to prime time and served as a thrilling climax. Both teams, like the others mentioned above, still have potential first-round byes and home playoff games at stake, but they will fight for them against eliminated opponents who may shift into evaluate-the-backups mode. Watching the scoreboards will be more informative and interesting than watching the games.

The 16-regular-season-game, 12-playoff-team format, which lasted from 1990 through 2020, created a delicate equilibrium that made compelling final weeks possible. Playoff berths were relatively scarce, while first-round byes were precious but reasonably attainable. The best and worst teams sometimes still had little to play for in their season finales, but there were still plenty of games between quality opponents with meaningful stakes in between.

The league upset that equilibrium by adding two wild-card berths and eliminating two first-round byes in 2020, then lengthening the regular season to 17 games this year. Division winners with no chance to claim a first-round bye, like the Cowboys and the Buccaneers, may still be motivated to earn a higher seed so they can face a weaker first-round opponent and perhaps gain an extra home game later in the postseason. But that’s not a very compelling hook for casual viewers.

The extra wild-card berths, meanwhile, turned the second half of the season into an endless round robin of welterweights who neither gained much ground by victory nor fell very far behind in defeat, making the games feel repetitive and insignificant. When every routine December matchup is a potential “playoff preview,” then playoff previews cease to be very interesting.

The latest Covid-19 surge made the end of this N.F.L. season feel even longer and less relevant. The Eagles and Raiders climbed past the Browns and Washington by defeating their glorified scout teams in rescheduled December games. Wild-card berths are not necessarily going to the worthiest teams this year, but the ones whose outbreaks were fortuitously timed.

Finally, ending the regular season on the weekend after New Year’s used to provide tidy emotional closure for weaker teams and their fans. Forcing the Jets and the Giants to endure another icy week of pointless football is a little like leaving the Christmas decorations up until the crocuses bloom.

The N.F.L.’s ultimate goal seems to be extending the regular season to 18 games, pushing future Super Bowls into Presidents’ Day weekend. Fans will then grow conditioned to accept wearying winter weekends of .500-caliber teams battering one another for the right to get routed by Tom Brady (yes, he will still be playing) in the first playoff round. The thought that a 17-game regular season was too long will someday seem as quaint and antedated as the Christmas Eve playoff matchups of the mid-1970s.

No matter how long the league draws out its season, fans are sure to keep watching. More than 28 million viewers tuned in for Packers-Browns on Christmas, with another 12.6 million flipping to NFL Network for the Indianapolis Colts’ evening game against the Cardinals. If a small-market, moderate-stakes, cable-tier N.F.L. broadcast like Colts-Cardinals can earn a 5.3 audience share on a holiday, Eagles-Cowboys will do boffo box office, Raiders-Chargers will do even better, and some future mid-January duel between teams with 8-9 records for the eighth playoff seed will still attract plenty of customers.

The N.F.L.’s audience never tires. Ultimately, that’s all that matters.