Simple, but wrong. The worst baseball teams generally win 40% of their games and the best ones 60%. The NFL has a much wider spread of outcomes. The Panthers have a .143 winning percentage - that would never happen in baseball. The worst WP% over the last decade in baseball is .450 (Rockies and Royals) and in the NFL is .397 (Commanders). Teams are more likely to make the playoffs in the NFL but that's because the NFL has a lot more playoff spots, to the point where teams with losing records make the playoffs. Finally, you can't ride one player to success in MLB. In the NFL you can just hire Tom Brady and make the Super Bowl.
Well run small market teams routinely make it to the playoffs in baseball (see Tampa and St Louis). In the past 10 years Arizona, Kansas City, Cleveland and Tampa have all made it to the World Series. In the past 20 seasons the Yankees have only won it all once.
There are some small market teams that really don't have a chance but mostly because their owners are not trying to win baseball games.