Where has he been shown to be a tribal? Certainly not through criticizing Islam, I hope, considering he's gay and would have every right to do so.
Well, for one, he called a reporter a "thick-as-pig-stuff media Jew", and although you don't consider insulting Islam to be tribal, it basically is, since ultra-nationalist douchebags like Milo tend to be the same guys that want to cut off aid to/refugees from entire nations and ethnic groups because of their Muslim majority.
Also, being gay doesn't justify being a hateful starfish. If you're gay, you don't get to call Christianity a cancer on the world. That's not acceptable in our society. But saying the same thing about Islam is suddenly justified because he's gay?