Priest has confirmed on his site that he wanted Triumph to be hated by all the other characters for "always being right" - which is an excellent formula for ensuring that all the READERS will hate him as well, since strangely enough, a lot of readers really aren't going to like a character whose core concept is "all the other established characters job for him, so that both the character and the writer can rub our noses in how much better the new character is" - and then, after deciding that he would make him hated, he decided to make him gay as well (also confirmed on the site), and certainly, there isn't anything problematic about THAT.
There's a reason why Priest will refund the money, on the spot, of anyone who walks up to him and says that they paid for his Triumph mini. When Priest is good, we get Black Panther and Quantum & Woody. When he's bad, we get Triumph and his utterly WTF story for Wonder Woman.