My experience has been similar. I think the biggest problem has been the evolution of the WebRTC APIs. A lot of code and blogs published pre-2019 are obsolete - they might have worked back then, but would need to be adapted for the current stanards.
The best resource I’ve found is Programming WebRTC: Build Real-Time Streaming Applications for the Web by Karl Stolley. (The book is still pre-release, if you buy it now it would be the beta version, but it’s absolutely the best that I’ve seen.)