I've done that myself too many time. I think the only problem with that in general would be if editing the prior move causes future moves to be illegal.
If I make an error 'playing in' an OTB game I just copy the PGN as is into textedit (or notepad, or your favourite plain text editor), make the edit, then paste the game back in and continue.
Digital Game Technology boards (DGT) record the games as they go. If the recordation is incorrect, then where all he broadcasting is, the operator can simply go back to the move and fix whatever hey need to change and walaah! The rest of the game loads on and no problem. I wish you that that could work on chess.com though.
I feel like in analysis, you should be able to right click on a move, and you should have the option to edit that move. (like how you can comment before/after, delete move, insert alternate line, etc.). When I enter games into the analysis that I've played in person, I usually either move the pieces on the board (instead of loading it as a PGN or FEN) And of course, occasionally, I make mistakes. It's super annoying when you're a 30, 20, (etc) moves into a game, and you realize you messed up a move 15 moves ago, and you have to delete it, and redo the rest of the moves up until where you were. Being able to edit the move would give you the ability to change one move, without deleting the notation that comes after it, or going into a alternate line.