It's not just LLMs, it's people doing that too— LLMs are trained on real writing in papers published in science, academia, and technology journals, as well as web pages and social media posts.
I've met real hard-working people who have had to change writing styles, because their style is too heavily mimicked by LLMs, so it now takes extra effort to not be accused of cheating.
You can use tools to detect the likelihood of text being written by an LLM, but as mentioned it will have lots of false positives in fields that significantly contributed to training data.
Your best option is to keep track of writers and journalists, who's styles you've appreciated, and follow them on whatever platforms they write for. Journalists often publish to more than one media outlet, and self-hosting platforms like Substack are growing quickly.
