Criticizing and attacking are different though. Also, a criticism based on ignorance, is different from just criticism.
Calling the Jewish God evil, or a demon god, can be seen as an uninformed attack on their beliefs, and in essence, an attack on them. Especially considering that it is completely ignoring the Jewish perspective, and their understanding of Hebrew scripture. That being so, it is intolerant.
Now, questioning or critiquing the Jewish God, if done in a reasonable fashion, there is no problem. Asking, why does it seem as if the Jewish God is evil, and then respecting the answers, is different than saying, you believe in an evil God, and thus follow an evil God, (which isn't far from calling them evil).
I really don't see why anyone needs to criticize other people's view of God though. I can't prove that the God I believe in is true. I don't even want to try. As far as I know, I could be completely mistaken, and there could be no God. Jews could be wrong, Gnostics could be wrong, etc. The fact is, no one can prove that their idea of God is correct, and thus seems a little ridiculous to attack others understanding of God then; especially since your idea of God could be well off base.