[throwaway292939]

This is likely untrue. I think tone is something ChatGPT excels at. The issue is more likely with your prompting. Sure, with standard prompting you'd get the "college essay" feel.

However, I do think long form writing is something ChatGPT isn't really able to do.

[getoffmycase]

The way ChatGPT writes drives me nuts in some specific ways. So I was messing around with it and asked it to specifically eliminate certain phrases it commonly uses, remove superfluous words, and modify the sentence structures in some specific ways. In the end it was surprisingly easy and fast to get it to produce writing at a significantly higher than 8th grade level.