No one these days wants to hold there hand up and admit they have made a mistake. It will always be someone elses fault, so unfortunately gesticulating at these people will always get an aggressive response.
I had a situation on the bike where a woman virtually ran me over at a mini-roundabout, so desperate to get past me and turn left that she pretty much side swiped me. I gave her the ‘shaky coffee beans’ symbol to which she reversed at me, got out the car and said it was a shame she hadn’t run me over before calling me a ‘disgusting little human being’ for making the ‘shaky coffee bean’ symbol at her. So, even though she had almost just run me over, then reversed at me, then said it was a shame she hadn’t run me over, I was the disgusting human being (she was in an Audi).
But, similarly you get it in the car as well.
Toot at someone who’s on the phone and veering into your lane – your fault & abuse.
Take evasive action when someone has straightlined a roundabout, nearly taking you out and give them a toot – your fault & abuse.
Toot at the person who hasn’t checked his blind spot and is pulling into the side of you – your fault & abuse.
No one seems willing to hold there hand up and apologise for being a dick.