If all vehicles are limited in the same way I am uncertain how this could even happen.

If the computer enforced max speed is 120km, and I'm going 120km, and the vehicle coming up is also going 120km, they can't overtake you, they can't close the gap.

Maybe, if the vehicle ahead of both of you is going much slower than either of you then yeah, they could close the gap. But even in that situation you could speed up to the max speed, matching that of the approaching vehicle, and merge. You'd still need to slow down to match the vehicle ahead, but so too would the one behind you, regardless of what you were going to do.

> If all vehicles are limited in the same way I am uncertain how this could even happen

This won't happen unless it becomes illegal to drive un-limited vehicles entirely though

People will drive older un-limited vehicles, or import un-limited cars from elsewhere, or buy limited cars and jailbreak them...

You're starting with a flawed premise and then concluding what you prefer

You're adding on a whole lot of edge cases onto an edge and coming to a conclusion that you think is best.

Some guy is shutting you out of the lane next to you, slow down and merge behind them.

Speeding up to merge with traffic that is moving faster than you is not an edge case :/

Okay, but that's not the scenario that was being discussed.