The language itself is great, but Microsoft the docs are sometimes horrible or outdated.

And most things feel like magic that you can't or don't need to understand. E.g. if you set up a modern asp.net project it's some huge boilerplate with configuration files and what not...

Also standards often change... E.g. try figuring out what the best GUI framework is to create a full-fledged Desktop app in C#. There's like a few different ones, and most are for basic mobile-style apps or not really mature. The best I found so far is WPF, which is kinda old though and everyone thinks it's dead.