Yeah but I believe he doesn't have that king of hate merch anymore (he once did, but nothing specifically refers to "The King of Hate" on his teespring store anymore, so just take my word for it, or someone here might know more about it than me).
The surprising thing for me that has gone completely under his nose is that he's been calling his website the King of Hate forums (and also his secondary youtube channel the King of hate vlahgs) for years now, and it's not particularly difficult these days to change the name of your website, or to be more technical about it, the domain name itself, on whatever platform you made that website on.
So I think if it really bothered him that much, he would have completely shifted away from that form of labelling, but he hasn't, for whatever reason that may be.