Cuz it’s could be an insult or a compliment, your performance decide, if you did greater than your equivalent on the other team then you shouldn’t be offended by it, yesterday I literally told my friend(who’s played Tank) before our game: I’ll write “tank diff” at the end no matter what so you should preform good, and he did! And it was a compliment.
So if you got offended by seeing it you should reconsider your choices in game and how you did preform
I don’t encourage using it, I just saying that you shouldn’t be offended by it