I was just curious about why you think this way. It’s not a big deal to anyone except you. The KDE team already has a deadline for new feature before a big release in order to have enough time for testing and fixing. And this wasn’t a big change or new feature so they decided to implement it. It’s pretty bold to assume this was a huge change. Both of us can go check the source code but I don’t care enough to do it.
The edit mode works a lot better now and it’s not as buggy from my experience.
If you really care about stability then use Debian or any other distro that delays big updates and does backports to fixes. Exactly like you are suggesting. If you are using Arch or any other rolling release distro then this is what you signed up for.