Speed limiters and cruise control are pretty common in modern cars. You can set your mental intended speed lower and won't drift as much. This is from experience of switching to a car with speed notification beeper (very low tech) - it took maybe 2 weeks to stop drifting over almost completely without paying extra attention. We ended up treating it as a game with gf - shortest time for a 300km drive with no beeps.
I have a modern car. 2015 Kia Optima, and it has basic cruise control. I don't know what conditions you're driving in, but I think it's fucking scary to drive with it on unless there's a completely open highway in front of me. Not controlling my own following distance feels like I'm about to hit the car in front of me at any given moment, especially on a road where the speed limit is 75mph and you have people going anything from 60-90mph.
Never heard of a speed limiter. As you can probably tell from the "freedom units," I'm from the US if that matters.
I pop the cruise control on lots, especially on motorways. If I get too close To car in front I’ll touch the break, but even in the U.K. roads are rarely that variable - especially near the speed limit.
The cruise control has a switch to change to limiter, I rarely use that.
Adaptive CC - yes, pretty much all the time. I understand it would be super annoying to use basic CC in the city. But that's where you can set the limiter instead (they often come together with CC).
