Isn't it still in deprecation hell? Do they even have a recommended proper own network solution?

Everytime I use unreal I'm blown away by how smooth it is (as long as I find what I'm looking for in their insanely huge toolbox), unity meanwhile just feels like constant roadwork.

What I hear from people who use it professionally is that it's constantly having features get deprecated, sometimes before they have a full replacement, that it constantly crashes and has various undocumented SDK behaviors (which sometimes change without warning), etc

Over the last five years it went from "not a professional game engine" to "a professional game engine". That doesn't mean it's a good one.