I am confident you can NOT turn that off.
I often find myself fixing little typos after the fact. Usually about 30-seconds after posting.
If I'm going to make a substantive change, I'll either do it in a new post, like Ken, or I'll at least make it obvious with a large-font "EDITED" notation. Some of it depends on whether someone has quoted from my post or not. But I do try to avoid the appearance of "changing history."
iClone 7... Character Creator... Substance Designer/Painter... Blender... Audacity...
Desktop (homebuilt) - Windows 10, Ryzen 9 3900x CPU, GTX 1080 GPU (8GB), 32GB RAM, Asus X570 Pro motherboard, 2TB SSD, terabytes of disk space, dual monitors.
Laptop - Windows 10, MSI GS63VR STEALTH-252, 16GB RAM, GTX 1060 (6GB), 256GB SSD and 1TB HDD