I must say that I understand your frustration, I am also experiencing that openhab is automatically updating itself, and that things are just not working after that, and that I will have to do some re-adjustments and restores and backups and backups of backups. And this now for a year and a half of using it. Somehow I manage to fix it all, just to discover that something else is not working then, and then I get a lot of recommendation to update to some dev version where it is fixed, but to expect some unstability as it is not stable version etc. So I do understand your frustration.
Having that said, I think that with openhab project and the community here, I for the first time understand the meaning of, as you say, expected reply “this is opensource, submit a PR”. Because, it IS opensource, and each and everyone of us using it can/should contribute somehow to the project if we want it to progress. Because that is the ONLY way any project can progress forward.
I was myself writing custom script when I started with automation, and then I went to domoticz, and come here, and added node red, and am now learning dockers and linux, and perhaps virtual machines and what not… All total overkill to achieve simple automation of lights, I am sure you see that I understand your point, a lot of wasted time for simple things.
However, only alternative I would eliminate this frustration is to, as you come to the conclusion, develop things myself and control it. But then some system update happens and I also have to fix some environment issue, and then I reaaaaaly want to use google assistant as I have it living room and also on my phone all the time, and to develop that integration I bet I would use 300x more time then fixing autoupdate, and docker, and java issues for openhab. And at the end, I would not be a google assistant master, and it will work well until the first time google updates something (and I noticed on my phone that assistant is broken after every time they update the assistant). And then I would use more time on that, and never get the time to integrate new Ikea switches that I really want to use as they are cheap and good enough for my applications. And if I would to develop that from scratch, I am pretty sure I would have a lot of frustration as “nothing works” with Ikea (again, each update from ikea something gets reset or missing or what not)… And there is vacuum cleaner, and the list goes on…
Much more wasted time here, and lets be honest, I would never make it work very good alone. This is where I would rather be a part of some team (any team), and the community here, both users and developers is something I never experienced on any forum/community.
I am not saying use openhab just because it is not the worst option out there, but you should consider alternatives before you just delete everything and starting from scratch, as anything pre made can get you up to 90% at the best.
I am afraid it might not be OpenHab that is under delivering, I know I am the first in line that is over expecting.
P.S. If I would to trade flexibility for reliability/convenience, I would consider Vera home control system.
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