Monetization is the easy part, a plugin that adds advertisements, paid subscriptions, or some other form of monetization could easily be made if there was a demand for it.
The real barrier issue is that of network effect. There's simply (almost) no audience, which means there are (almost) no creators, which means there is (almost) no audience.
I've been publishing my videos on my own peertube instance for a while and I really do appreciate it as a platform, but I don't think that the technical aspects of it alone will ever be the key to its potential success.