1. Sure. You might not see it because you're a fan of his content, but he made his bones being overly critical of WoW and not in a constructive way. That's why Blizzard excludes him and certain other personalities from the community, but works with other personalities that are equally qualified and provide their criticism in a more civil and constructed manner. If you're not even going to acknowledge the simple fact that they work with other people that are critical of their games we can't have a discussion on it. The difference between those personalities and Preach is that Preach's criticism isn't constructive. His feedback isn't nearly as useful as he and his fans think it is. Great he likes the occasional thing, wonderful. Oh look he thinks these 12 other things are shit and he's going to list off why he personally thinks they're shit, and that's fine-ish, but then he goes into a rant about how grossly incompetent the developer is and he crosses that line and self sabotages and that's why they won't touch him. Why work with that guy when you could work with any number of equally qualified other people that will tell you what's shit about your product but not launch into a spittle-launching rant about how much of a knuckledragger everyone at your company is?
2. Well that's your definition of casual, sure. The industry definition though? Not so much. By your definition someone in the top 5% could easily be a casual because they just login for raid time and their guild provides all the consumables. Casual is a lot more difficult to define than time spent. I've had casual friends over the years that have spent much more time in-game than I have as a Mythic raider but they never moved beyond LFR or really did much beyond pet battles. By your definitely they wouldn't be a casual. I love that in your mind you truly seem to believe that any definition other than yours is wrong and you think you can qualify that by saying that you work in the industry. If your "facts" that aren't facts are something that you're holding on to that dearly and you admit that nothing will change your mind because your opinion is law in your mind, why are you even posting on a forum? How can you expect to have any sort of useful dialogue with a stance like that?
3. Unfortunately I watch a lot more of his content than I would like to admit. It's pretty entertaining even if it's not really any more valuable than any of a dozen other content creators. He's essentially an angry Towelliee in that regard.