But that's the problem. Unique, quirky mannerisms become polished out. Flaws are smoothed and over sharpened.

I'm personally not as gloomy about it as the parent comments but I fear it's a trend that pushes towards a samey, mass-produced style in all writing.

Eventually there will be a counter culture and backlash to it and then equilibrium in quality content but it's probably here to stay for anything where cost is a major factor.

Yeah, I suppose that would be an issue for creative writing. My focus is mostly on scientific writing, where such mannerisms should be less relevant than precision, so I didn't consider that aspect of other kinds of writing.

And I the only one who doesn't even like automatic grammar checkers, because they are contributing to a single and uniformly bland style of writing? LLMs are just going to make this worse.

Sure, but Grammarly and similar have existed far before the LLM boom.

That's a fair point, I only very recently found that LLMs could actually be useful for editing, and hadn't really thought much of using tools for that kind of thing previously.