They very much DO test exhaustively before release, and there are a LOT of people looking, for a decent amount of time beforehand, but we can't catch everything, and sometimes things we do catch take a while to resolve, and sometimes those resolutions can't make nearby release date but are in progress asap and will probably make the next hotfix, or triannual update after that.
Personally I think 2 things are different now to previous years - Firstly, 2024 is the first year a whole load of stuff went multi-core, so there was orders of magnitude more functionality to test and secondly, since we went subscription-based the speed of development has accelerated to try and justify that, and to deliver 3 larger scale updates per year, which I guess must have some effect on pre-release test time available.
There are millions and millions of lines of code in Cinema now, and it takes a little while to find ALL the circumstances in which new stuff doesn't work with old stuff etc. It is an almighty leviathan of a task to try and stay on top of. Not an excuse, just a fact. It doesn't mean they don't try damn hard - they really do.
But of course equally I also understand the frustration people feel when stuff doesn't work (and I am certainly not immune to that myself), so you have my full sympathy...
I can't concur with your thoughts that 2024 isn't production-ready though. I use it every day (though not in quite the same ways and areas as you by the sounds of it) but I haven't noticed a general degrade in performance or reliability overall - quite the opposite in some cases, for me it is noticeably faster in a quite a few areas
, fixes a lot of modelling problems that were still hanging about in 2023, and stabilised a lot about symmetry, simulation and pyro etc etc.
Display crashes still continue though, much to everyone's annoyance, though even they tend to happen in later versions in a way that at least lets you save the file before restart...
CBR