YouTube playback issues will occur every so often, even after the rewrite. They’re not using the official YouTube API and rather scraping youtube.com, to avoid what happened to Twitter and Reddit apps.
Downside is, if Google changes the YouTube webpage, there’s potential for breakage and NewPipe needs to be updated.

If you install it via this F-Droid repo, you’ll get those updates much quicker, though: https://archive.newpipe.net/fdroid/repo/