There is a program built into Whonix, I believe it's called Kloak, that randomizes your keyboard input times so you can't be identified via keystroke timing JavaScript. There's also research into defeating stylomeyric analysis such as anonymouth but I'm sure there are plenty of new tools, if anyone find any that work well please reply here as I haven't looked in some years. 'Stylometric analysis' is the key phrase to search for.
With AI this will get worse (better identification based on typing styles) but it will also get better because you can setup a local LLM and ask it to re-write your text in a certain style. Touching on this, everyone uses a combination of unique phrases and misspelling or mis-spelling (see?) of words, and with enough text from a given account the chance of statistical probability in attribution is very high. It's how the Unibomber was identified after his manifesto was published, because he used a very specific phrase incorrectly and his brother recognized it, so his wife convinced him to call the FBI tip line about his brother.