Shitloads.
Most people don’t write particularly well. That’s not a criticism… we’re not really taught to, more often we’re taught how to write badly (to sound ‘academic’). So along comes AI and everyone says ‘wahoo, you can use this to help you write’, and people do. We’ll often be reminded to check what the AI does (“AI first, human last”) but I don’t think all that many people do that, and of those that do… well a lot of them are using it because they can’t write well and that probably means they’re not super equipped to assess what the AI shat out.
LLM’s are shitty writers out of the box, but better prompting and reviewing can get ok results… but I’m not sure what the point is because a good writer can get better results faster by just writing, and a bad writer lacks the skills to get good writing out of the LLM. The net result is that nothing changes for the good writers, the bad writers think they’re delivering good writing but they’re not, everyone is having to read generic padded-out slop everywhere, and it’s cheaper to replace a kidney than a stick of RAM.