Sorry for not getting this point clear
Yes - the API (the protocol for app-system communication) instabilities between betas can be frustrating for developers and sometimes (and there’s a lot of these sometimes) there are annoying regressions which work in one beta and break, then suddenly work again. If one were to spend time trying to fix these, one wouldn’t achieve much. It really depends on what the developer is fixing.
It’s entirely possible that an app doesn’t Break during any of the betas except the final beta, which may or may not be the GM OR it might break in the GM and not in the betas (I’ve had that before).
What I’m saying is that broken apps during beta phase isn’t a clear indication of whether they’ll be working at the GM time.