I don't know if I would say we are at crisis level yet, but like many others I have definitely noticed a shift in attitude. We have longtime dedicated users leaving/retiring with no plans to recreate and many cite the same reasons for it.

It's hard to motivate people by saying "well maybe in 5-10 seasons after the rebuild we will be good enough to compete, but in the meantime it wont be pretty" With how long it takes to turnaround a roster, people are getting burnt out waiting to finally be good.
It's also less interesting seeing the same teams on top over and over again. Sure one or two might phase in an out over a few seasons but feeling like the end of the season is already predictable makes it harder to care about what happens in a season. No one wants to go watch their team get stomped in the sim over and over again.
Many of the recent GM step downs have also cited the same burnout, stress, and lack of enjoyment. I know by the end of my tenure I found it hard to care anymore because nothing I tried to do seemed to make a difference.

I would say rather than a crisis, we are at a crossroads for the league. It can go in a few different directions, but where it goes will determine if people want to continue to engage with it or not.