Notion I agree but it does have a way to lock a page so you can explicitly unlock it to make edits, more clunky than having a “suggesting mode” but it works.
And both product actually have history so if you do accidentally blow away something or add garbage you can revert to the version before you made accidental changes.
[0]: https://esa.io
2 months ago I found a good alternative called ERA. It is targeting developers and their needs (as far as they market it that way).
It's currently free to use as it is in beta, but for me it offers everything I need.
To me, it's just barely short of a moral principle that software should never accidentally lose user content. "Crash-protect" is only adequate with a very broad idea of a "crash". On mobile or in a browser tab, the app might get killed at any time to save memory. Am I going to go to Wikipedia on my phone to get some info for what I'm writing in your app, and come back to find a blank text box again? Or if I get distracted in the middle of it and then have to reboot my computer fit an update? These might look like orderly shutdowns, not "crashes".
I'm happy to have my opinions considered, but I would caution against overfitting to them - most people don't seem to like the UX that I like.
Also, I think a lot of stuff that winds up in Notion, in the contexts where I have used it, would do better living in the relevant repository so that changes to docs can be better tied to changes in the code.
Also also, every time I use it I wind up with The Hues Corporation's Rock The Boat in my head, and while I like the song it shouldn't be on loop in my head more than once or twice a quarter please.