The first people to jump ship are going to be the ones who already desire something "better" than the current environment. Those who haven't yet jumped ship are the ones who are not (yet?) dissatisfied enough with the current environment to make a change.

If enough of the "early leavers" manage to coalesce around the same new space, then that new space is instantly noticeably "better." On the other hand, because those early leavers are a very small proportion of the place they are leaving, the old place doesn't change much. Even if the rate of that change does increase, that rate change may not even be very noticeable (although I have already heard of an uptick in pro-company rhetoric at reddit).

As I recall, this is precisely what happened when Digg began its collapse, and many people abandoned Digg for Reddit. Reddit was instantly a much better forum than Digg had become. Now the same thing is happening again, well, not exactly.

Digg declined because it was a silo, and because corporate interests needed to monetize it. Corporate interests made decisions that they felt went in the direction of monetization, with disregard to the overall user experience. Reddit is also a silo, also operated by corporate interests, who are also making decisions they feel are in the direction of monetization, with disregard to the overall user experience. The difference today seems to be that the place people are jumping ship to is not a silo, and is not operated by corporate interests.

It'll be interesting to see where the fediverse goes, and how this landscape develops. With beehaw defederating from lemmy.world and sh.it, it's clear that it would be possible for corporate interests to operate their own instances, and only federate with "approved" instances - a fracturing of the fediverse, and a "re-siloing."

In the past, it took a long time and was quite difficult for users to abandon declining siloes. The fediverse makes it so much easier for people to jump ship when that becomes necessary. Corporate interests take note.