[Russell Sobie]

The rules are pretty sparse on SRS so basically anything the game lets you get away with is fair game... and I don't know of anything in the game that prevents flashing lights to be annoying.

Turning off post processing practically renders them invisible.

What I mean is, there's no game mechanic programmed into Assetto Corsa that prevents people from flashing their lights in an obnoxious way outside of the "valid" reasons I've listed for flashing. So basically everyone is free to be headlight happy if they so choose.

But yeah, if you are one of the drivers that find people behind them lighting your backside, I suppose turning off post-processing might be a good way to not feel the pressure. But then how would you know that the guy behind you is SO ANGRY!