I wonder what percentage of its users know what the GPT stands for, or even thought about it for a second?
chatgpt is generic (as in, no prior meaning attached, except for the few people in the world who understand what GPT stands for). It's simple - even a non-english speaker can say it easily, and doesn't require one to be native to know how to pronounce it (this is a difficult concept for a native english speaker to grok).
These features makes for a good name.
So i argue that chatGPT is indeed a good name (as good as google was).