Also, I am not sure if it has my writing style preferences saved somewhere, but Claude uses the terse style I prefer to read explanations in, without me needing to mention it. ChatGPT can do it too but it needs to be prompted lest it do the whole "repeat question, bullet points, summary" ceremony. ChatGPT gets really annoying when you have do the "slightly more detailed, slightly more terse, there we go" ceremony as well. For similar reasons, I prefer it for code.
One place where ChatGPT absolutely takes the cake though is mathematical proofs heavy with symbols. Nothing else comes close in my experience. It's also better at latex typesetting (seems to be more fluent with common packages like amsmath).
So I think it’s mainly to work with the one which works for you. I’ve seen some of our more junior developers first use Claude and then ChatGPT to refine their output, or the reverse.
As other commenters have said, that is just my personal opinion, I have zero evidence to back that up lol