There are plenty of reasons to believe the former rather than the latter. The Niners could easily be 8-4 and have control of the NFC West if they had simply not blown three divisional games this season. If just a few things go differently, San Francisco would not have choked away games against the Los Angeles Rams, Arizona Cardinals, and Seattle Seahawks.
San Francisco still has a lot of solid pieces. The offense has been able to move the ball well for the most part, but the red-zone efficiency has been abysmal. Head coach Kyle Shanahan is a smart enough offensive mind to figure that out.
The defense may be a little bit of a tougher fix, but the 49ers will still have two of the best defenders in all of football in Nick Bosa and Fred Warner next season.
That is the sunny appraisal, now for the doom and gloom.
Perhaps this is not an anomalous blip of a season. Maybe this is the beginning of an inevitable decline of an aging corps of players worn down by four absolutely heartbreaking playoff losses in a span of five years.
Not only are their bodies wearing down, but their spirits may be wearing down as well. How many heartbreaks can the 49ers take before they start to question whether they can actually get over the hump?
Maybe the juice is gone. Perhaps Shanahan has lost his play-calling edge and has become predictable and stale to the rest of the league.
Both of these futures can be argued for. Yet, the former seems more likely. The 49ers can use this year to reset. By sitting on the couch for most of January rather than playing deep into the playoffs like they have each of the last three seasons, the Niners can get their minds and bodies right. Sitting on the couch and resting, they can watch other teams play playoff football and get hungry.
This season has been simply brutal in every way for San Francisco, but there is plenty of reason to believe this is not the end of the Shanahan era.