Driving home one night, lots of traffic on the highway, and I notice I can't see the headlights of the car behind me they are driving so close to my bumper. So I ease off the gas and as soon as I can move over to the right. (Note, I was keeping up with the traffic in the left lane, I just wasn't riding their ass considering we're lined up as far as the eye can see)

This guy passes me and pulls in front of me, only to break check and slow to a fucking crawl. Left hand lane is still full, so once there's an opening I move over and accelerate so this asshole doesn't have room to get in. Traffic lined up behind me too so I have no idea how long it took him to get back over into the left lane. For someone so damn impatient he ended up wasting his own time for no reason.

All this is to say:

you're not a traffic cop

Neither are you. It's not your role to "punish" people who weren't moving fast enough for you. Just move the fuck on.