I think you make a good point regarding support. This is, for businesses, the crucial issue. They want to buy reliance, support and certainty. This is what commerce, like Microsoft, offers; peace of mind for (big) bucks.
Organizations can't easily take measures to assure proper support for a lot of open source software. They'd have to hire and probably educate a lot of expertise, which all has to be managed too.
It's just a whole lot easier for decision makers to spent extra money to have a contractor solve any issues, or at be able to blame (sue) them.
This is quiet an unexpected turn of technical advancement. I can see people would actual watch this if it's the only available or affordable alternative. The enshitification continues...
This is close to my personal take on the subject; "you don't turn on your signal for the car you saw, you do it (especially) for the car you didn't see"
Yeah, I just finally updated the last remaining servers to bookworm this weekend, so a next release is probably coming soon. Proven by earlier experiences
https://en.wikipedia.org/wiki/International_Fixed_Calendar