You can browser the countless HN or even Reddit threads and it's always filled immediately with one of the few standard explanations (which are all in the Monty Hall Wikipedia article). None of the "endless discussions" actually disputes the strategy or nobody needs to be convinced. It's all about whoever things they can come up with the most "intuitive" explanation. At this point I'm starting to thing that it's more a myth than reality that it's "not widely believed".