That's not like a widespread/by-default/de-facto standard across the ecosystem, by a wide margin. Browse popular/trending Python repositories and GitHub sometime and I guess you can see.
Most of the AI stuff released is still basically using conda or pip for dependencies, more times than not, they don't even share/say what Python version they used. It's basically still the wild west out there.
Never had anyone "frown" towards me for not using MyPy or any typechecker either, although I get plenty of that from TS fans when I refuse to adopt TS.