I like Joe Rogan's podcast. He often gets very interesting guests, seems genuinely interested in them, asks interesting questions and let's them talk at length. He's perhaps a bit 'conspiracy theory'-heavy for my taste but whatever - I enjoy his podcasts. So, I also wanted to enjoy this show and I'm not here as part of a "review bomb."
In short, Joe Rogan just isn't funny. He doesn't have "funny bones" or natural wit and he can't improvise. If a joke tanks (and many do in this show) he can't pivot to a fallback as even very-average comics learn to do. If he does come out with a smart gag, he will kill it with his delivery. He has weapons-grade confidence, but that won't save any set he does.
He's got a huge following but so did Dane Cook. There's a phenomenon where unfunny people can, by sheer force of will, generate a following. As someone who admires Rogan for his thoughtful, insightful podcasts, he really, really needs to stop doing stand-up.