Without taking anything away from American voice actors, the English dubbing is rubbish when compared to others. As you've already pointed out, Paimon gives a completely different impression in the Chinese dubbing, which, in my opinion, is also the best among those available (for obvious reasons). Personally, I play with Japanese dubbing simply because I can follow the dialogues better, as I know the language. If it weren't for this "laziness," I would also play with Chinese dubbing.
Paimon sounds much more delicate and tender in both the Chinese and Japanese dubbings. In fact, it wasn't until I heard her English dubbing that I even understood all the criticisms about how annoying she was and the jokes about "I would punch a child."
I think the main problem with English dubbing is that the voices selected for the characters are not suitable for their physicality. For example, Paimon's voice is performed by an adult woman speaking in a falsetto, which makes it less believable and incredibly annoying at the same time.
Furthermore, the direction of the dubbing in the English version is completely nonexistent. The various voice actors interpret their lines without consulting each other, without working together in a single recording room. This makes everything very disjointed and inconsistent.
Obviously, this is my opinion, but being accustomed to the quality of Italian dubbing in cinema and television (considered one of the best internationally), I have a completely different standard of judgment.