IS explains why they’re so loathsome in an article. They make a list.
One is because you’re kuffar.
We hate you, first and foremost, because you are disbelievers; you reject the oneness of Allah – whether you realize it or not – by making partners for Him in worship, you blaspheme against Him, claiming that He has a son, you fabricate lies against His prophets and messengers, and you indulge in all manner of devilish practices.
Oh, more than that – I hate him, and I say he doesn’t exist and never has. I hate the fictional character, and I don’t for a second think he has ever existed. I blaspheme against him all the time. I also don’t … Read the rest