No matter the situation if you are too close to the vehicle in front of you, then you are the asshole.

I think its appropriate to go slower when tailgates, because you need a stopping distance for safety. If the car is so close to you that they're not giving you one, slowing down is how you create one for yourself. If the tailgaters backs off, you can safely gain speed again.

The method I was taught was to control the distance. If someone is too close for the speed, it needs fixing. I can't adjust the distance, but I can adjust the speed. Basically, slow down until the distance is now appropriate.

Most people seem to get what's going on quite quickly.

I prefer to speed up for a few seconds then take my foot off the gas. Usually at this point they'll be speeding up but will have to hit the brakes. Rinse and repeat until they go around

Yeah, I'm sure the events described in the OP post were satisfying on some level but a crash is a bad outcome and intentionally antagonizing the tailgater probably made it more likely to happen.