I am not sure how many times I've been mistaken for ChatGPT, but I don't think my writing style is actually very similar.
I'm pretty sure that when people say that, most of the time, they actually mean, "I want to disagree with what you're saying, but I lack the ability to do so legitimately. If I simply accuse you of using an LLM, people will assume I'm right and I will 'win'."