To me it still literally means Shut The Fuck Up, and whenever I see it, my immediate reaction is that the person on the other end actually meant it exactly as rude as I have always perceived it all my life.

even if they does it mean exactly as rude as you perceive it, does it really matter? you will never be liked by everyone. so if it is situation where you can just shrug your shoulders and leave, it may be time to do it and don’t take it too personally. the person on the other side can be 7 years old. if it happened in real life, would you spend time discussing with him?

if you see a person with a sign about the end of the world coming tomorrow looking moderately insane on the street, in real life - do you go to them and try to convince them they are not right, or do you just shrug your shoulders and move on with your life? and why do we often act differently online?

to be clear i am not trying to be holier-than-thou here, i’ve been guilty of exactly this many times myself, but it is at least useful to be aware of this in retrospect.