He just doesn't do it all the time with every guest and topic; but that's a side-effect of having long casual meandering conversations so people get upset when it doesn't happen with intensity they want against the content they disagree about.
Rogan has expressed many strong opinions and has changed those opinions over the years. He's definitely not a nihilist and very clearly leans left on most issues with a few conservative points regarding individualistic rights and personal freedom. He also hosts many interesting people from many disciplines that I've learned a lot from.
It seems like you've never actually listened to any episodes and your comment represents the ignorant and shallow views that people accuse the JRE show of having.
"Forgive him; he is a barbarian, and thinks that the customs of his tribe and island are the laws of nature."
People are so used to shows and popular voices pushing agendas that it seems they're flummoxed when one isn't doing that. Apparently under the impression that Rogan is endorsing everything his guests say and that his listeners just blindly absorb/repeat.
But he isn't pushing an agenda, isn't telling you what to think, doesn't filter by ideology. He's just having conversations with people that he thinks are interesting and treats them respectfully, like a friend would in real life. That's why it resonates, is refreshing, and will continue to mystify those that expect everything to fit neatly in a pre-defined, pre-approved box.