Aside from saving time, I'm bad at writing. Especially emails. I often open ChatGPT, paste in the whole email chain, write out the bullets of the points I want to make and ask it to draft a response which frames it well.
Hopefully you're specifying that your email is written with ChatGPT so other parties can paste it back into ChatGPT and get bullet points back instead of wasting their time reading the slop.