To Rogan's credit, he was early to the concept of video podcasts, which Youtube's algorithm picked up on after they lifted video time limits in 2010 (or thereabouts). His videos were so long that he also profited handsomely from pre-roll and mid-roll ads that Youtube started introducing early in the last decade. Finally his popularity exploded once he started delving into "pop culture commentary" and "conspiracy theories" in the mid-2010s.