Oh, it is a general nuisance for many webpages that have forms. But at the same time, accidental tab closing does not happen that often, and many sites (or the browsers) do save drafts. (Which is why I see the bigger nuisance in sites that pester you when you try do close the tab ;-)
I even remember seeing this happen on itch, but I do not know if that was something the browser did, or if the draft was temporarily saved on itch. I am logged in after all, so that would be possible.