It's because these aren't sports teams. There are real, honest-to-goodness humans dying by the tens of thousands right now. Humans who have been treated horribly, for decades, by both Israel and their various leaderships, especially Hamas.
This idea that you need to pick one side over another, that if you criticise Israel you must support Hamas, is completely ridiculous. Both leadership have done terrible things. The innocent people in Palestine and Israel don't deserve to be killed over those things.
So yeah, it's not a question of which country would be nicer to me. I've been to Israel, I loved it there. I loved the people too. That doesn't change the fact that what their government is doing is wrong.