If I disable it, I can only use source mode to edit the page. Classic editor has 2 parts, visual and source. I use the visual mode when I create the the new page or edit if I can use, but I use the source mode in "Level Walkthroughs" because the templates are stacked, so I can't switch to the visual mode. (Classic is more convenient.)
Sorry for the late reply. I feel that although it's more user-friendly, it's more troublesome when trying to edit from source mode. I'm used to placing brackets and braces, and Visual Editor won't let me do that. But that's just my opinion.