What is it that he has to make up for? His guests cover a pretty broad spectrum. This is a genuine question because I haven't actually heard him push anti-vaccine sentiments, unless expressing an opinion is what you define as pushing. Or maybe he's gone beyond expressing opinions and is now seen as some kind of authority on the subject?

Unfortunately “expressing an opinion” == “pushing” in the minds of many people these days.

He's got an audience. Expressing something becomes pushing it when you're telling to a large audience that trusts you

I disagree strongly. I believe in intellectual agency.

Where should the line be drawn?

That really has more to do with a vocal minority that worship Joe Rogan, than what Joe himself has pushed. Any celebrity is going to have a group that takes what they've heard and blows it out of proportion.