I don't mind that they wanted to protect their channel name and brand, but i think that this is pushing the Boundaries of what I can call "protection". Their isn't really much information on what constitutes their "format" either. Plus trademarking the word "react" in video names is far too overreaching in my opinion.
I don't know if they deserve this much hate, but I can say that hopefully it serves as a lesson to other content creators on the Do's and Dont's of IP law.