First, there is no reason to accuse Apple of anything sinister, they are simply having some teething problems with their last two Mac OS systems. There have also been some unwelcome changes to Safari and some other applications. It may make sense for Apple to follow that old adage: If it ain't broke, don't fix it. Added cool functionality is great, but if people are used to a certain layout, don't change it, it will only irritate people, who will now be making mistakes. Apple could certainly improve on its Mail application. It would be nice to be able to create "archive folders" for various email exchanges. Also, there have been other problems, the ones I don't want to mention for a reason.
One great feature of Apple software has always been that transitioning to a new revision has always been easy, so keep it.
That said, I had one crash where Beta 8 failed to install, leaving me with a corrupted SSD. At first I tried to recover using Time Machine, but this too failed, and some of the error messages made me feel that my TM got corrupted too. In the end I had to use Apple Internet Tools to reformat SSD and reinstall from Internet, and the TM survived intact. Out of fear, I am now going to keep two different TM backups. That Beta 8 bug is a clear indication that something serious escaped someone's attention, and that someone pressed "return" key too early. Unreasonable deadlines for instance do this to people.
Mac OS is great, but Apple has managed to set a high standard for itself, and lately they seem to have a problem meeting it. Public Betas are not intended to be problem free, and we all expect them, but something like Beta 8 should have never happened.