I work in the AI field and ChatGPT is a company that's not our competitor but we are in awe of its incredible technical achievement. It is the next step in AI and it's making massive strides.
I'm having the same type of discussions you write here with fellow Medium writers and this is a "shot across the bow." I wholeheartedly agree with you, it has no voice and certainly NOT your voice BUT, here's the big but, it will get there.
The differences between ChatGPT3 and ChatGPT4, released 5 months apart, are almost night and day. It's vastly better, and I believe "not having a voice" is a technical problem the AI engineers will solve in time.
I believe, just like with the Medium text-to-speech reading ability, you'll be able to pick a predefined writing style with ChatGPT in the future.
It's not here yet, but expect it to come. This thing has legs as a research tool, a method to overcome writer's block, and a writing assistant. Use it for such and it can make you way more productive.
My 2 cents.