[Put a bad "your mom" joke here]
That should do the trick!
A bit more seriously, though, I agree. It's your choice to be offended, it's your choice to get angry.
Sure, there are cases where some (extreme?) things shouldn't be said, but there's only a handful of them.
Over the years of playing this game, I've seen people get buttmad about things, that are a part of human's life since the invention of the wheel, that they are in 99.(9)% of cases familiar with and come across them daily (unless you live in a basement). Shop, school, home, street, ice cream stand, you name it.
For some reason they come home, start LoL and get angry at even the slightest annoyance they see.
Here I am sitting wondering why I got chat restricted ~3 months ago for pointing out a dude who instalocked mid lane and went 0/5.