It’s a leftover from reddit. A comment would be marked as “edited” if you changed anything after posting it, and since some people are shitheads and change their comments to say completely different things after people have already replied to them it’s just a way to inform people that the edit you made to your comment was just to fix typos and not anything significant
Lemmy posts also show they are edited.
Though I never wrote that I fixed a typo on reddit either. Only stating the edit if it was adding info or changing something.
I leave spelling mistakes once somebody replied and no comment about fixing it before that.
The only problem is if you accidentally include some personal information or other type you don’t want to be out there and you’ve edited it out, you probably don’t want it to be accessible.
Or people can change their comment and leave in “Edit: typo” to throw people off their trails, like I just did.
What, did you think I was gonna be deceptive?
EDIT: Typo