A cynical view is that it's not just 2-3 providers, its any competition to their cloud-hosting business. See for example the recent wordpress drama, which concerns a small competitor.
SSPL and related licenses are ambiguous and scary enough to ward off anyone potentially competing with the copyright owner, and I doubt that's seen as a downside.
This is a really good example of why software with a license that is basically "this could hurt you but, like, trust me bro" isn't worth building with/extending/learning. It feels a LOT like a landmine waiting to detonate.
Even if I'm doing completely non commercial work I never ever ever will want to productize in any way I'd rather build my skills and familiarity with something portable (and I don't want to have to remember when I can and can't safely use each part of my stack). Anything else is just asking for a future nightmare.
The oracle and wordpress stuff recently are devastating. Can you imagine having to grind your entire company to a halt looking for anything that uses anything that uses anything that uses redis/java/whatever?
I'm an engineer. I can't justify a fixed amount of upside for an unbounded downside if I ever get on some stranger's bad side for whatever reason.
SSPL and related licenses are ambiguous and scary enough to ward off anyone potentially competing with the copyright owner, and I doubt that's seen as a downside.