Simply put, he alienated a lot of People in the industry and continues to hang around with some of the worst critics I've ever seen.
It's a Shame really as I recently read New X-men and I really liked the work he did on that. Although knowing who he is now, does make him working on something like X-men extremely ironic. Especially working with Morrison.
My advice is, don't follow the guy. You'll just get sucked into the rabbit hole which is the shitty side of YouTube.