Yep, I'm sure he's bitter, because when it was 'his turn' he lost, and Trump got elected. If he feels Trump is "poorly informed" then why doesn't he inform instead of snipe at him in the media?
That is a sort of RINO's creed. Every time McCain, Graham, and all the rest, have something to say, they never say it to Trump. Instead, they run to media. And, not just any media. You will find them on CNN, MSNBC, Politico, Huffington Post, and all the other Leftist outlets, trashing Trump, his administration, and sometimes his family.
This is how they score points with the Left. They are soooo desperate for the Leftists to love them, they'll do or say anything to get their approval. On the other hand, they have no problem disparaging and insulting their own base. That's just who and what they are. They are self-hating Republicans. The idea being, "Yeah, I know I call myself a Republican. But I'm really with you guys. Please like me. Please love me!!!!"