Anecdotally, I've been aggressively fed ads and suggested videos for Joe Rogan content for probably about five years now.
So I'd guess it's in large part because hellsites like @TeamYouTube have been shoving him down people's throats for ages.https://twitter.com/JaBogen/status/1163427505019203586 …
I’m a faithful listener to Maron as well. He’s usually a hit with me. Rogan is a miss like 99% of the time. But then he’ll interview Cornel West and I’ll listen and it’s a home run.