I have tried using peertube a couple of times, there are some good videos there but it's also a place where, and this is my personal opinion, the wackadoos gather, because there's less quality content shouting them out.
It could be a viable YouTube replacement but it needs a lot of independent server hosts federating the content so that you get quality of speed and playback and it needs more people posting content to that.
In other words it's halfway there, but it needs participation, money and development to get the rest of the way.