Is Phil really that terrible?

This was probably asked before but I recently saw a video on TikTok and went down that rabbit hole. Turns out tons of people absolutely despise Phil and want Claire to divorce him. But for the love of God I can't figure out why. I saw a comment with several thousand likes on it that had a headcanon that later on Haley and Alex helped Claire divorce Phil because they hate him as well. Now they are obviously allowed to have that opinion, but can someone tell me whats the basis of it?