I suppose this is rhetorical, but to answer anyway - joe rogan prevents that. He’s in charge of who he has on as guests.

But even if he did, I suspect his ideology is such that scientific knowledge is de-valued over anti-establishment takes, and so nobody would listen to that healthcare expert. Because it’s not like his listeners haven’t heard that vaccines are effective - they just believe him as a source more than they believe any expert

He has Sanjay Gupta on, a well known doctor that supports vaccination. Even Gupta couldn’t make a firm argument that everyone must get vaxxed, even with the fact checking in real time

Did you just move the goalpost? All you need to make a firm argument for is that “getting vaxxed is safe, protects you, and protects others” not “everyone must get vaxxed” - nobody can make that argument - there are too many people unable to get the vaccine for valid medical reasons.