the content seemed to be less visible even to his subscribers
Am I the only one who still uses the subscriptions page? I get a chronological list of all my subscribed channel's video releases. I have seen zero indication that I'm missing anything at all, and I fairly frequently go to channel's pages to check that my subscription list is complete.
I've never clicked a single notification bell, and don't rely on the home page's recommendations/sorting, unless I'm actively seeking out new recommendations.