I'm guessing you are aren't aware of Coast to Coast AM?
Art Bell was entertaining and interesting. When you listened to Art, it seemed like you got a good source of entertainment like a decent tv show and it was nothing more than that. But once Art left, Coasy to Coast really changed to a more conspiracy based show and this helped open up and expose people like Alex Jones to a wider audience. Art had built the audience up but once he left that audience didn't disappear over night. So with that exposure, people like Alex Jones could grab a part of that audience and hang on for a while before greater times for conspiracy and that is happening right now with Trump in office as conspiracy theories seem to be the normal things these days. Conspiracy used to be its own little niche but now it's really out in the open thanks to the Internet and programs like Coast to Coast.
I think it suggests the public's desire to consume kooky conspiracy crap has always been with us. Sure it's come a long ways since Art started his broadcast in the 80's but a vein of gold that has always been there for the wacky or unethical to mine. Art seemed like a gentle soul, Alex Jones seems like a total bastard.
This is probably giving the conspiracy 'community' too much credit, but we desire mystery. We desire myth and legend. We live in an era where all the great myths have been/are being torn down. All that longing for the mysterious has to go somewhere.the public's desire to consume kooky conspiracy crap has always been with us.