Honestly having occasionally glimpsed the logged out YouTube page which appears to do this... I'm glad that I don't have to deal with that either.
As for what they should do, I think populating the homepage from the subscriptions list (either literally as an ordered list or by some algorithmic "watch time vs average watch time for this creator", I don't care) would be preferable.
If the goal were anything but discouraging disabling watch history, they’d take care to design a page not so strikingly barren.
Video categories, subscriptions, trending searches (not saying we’d WANT that), Google-curated selections, recommendations based on user choices (“what kinds of videos should we show you, want daily news/sportballs/music recs?”)
As for what they should do, I think populating the homepage from the subscriptions list (either literally as an ordered list or by some algorithmic "watch time vs average watch time for this creator", I don't care) would be preferable.