Adaptive cruise changes it completely! It exists for that exact use case. It makes cruise work in the scenarios where cruise doesn't work. It cuts the fatigue on long days on busy motorways by a very significant amount. I did 9 hours in a Velar in a single very busy day in the UK. It felt like I'd driven 3 hours in a normal car.
And on the complete opposite end of the spectrum I drove a Morgan Plus 4 for 9 hours in a single day and it nearly killed meEpic car though.
I don't understand people who say they can't use standard cruise, I always use it on the motorway, as long as you're aware of your surroundings there is rarely a time where you need to completely disengage it, I can drive for hours just slightly adjusting speed on the steering wheel.
I found it better when the motorway was heavy with traffic. It was very annoying when it was more free flowing because it would react to the car in front to early, even though I had it on the shortest distance.
I had it in a VW passat and whilst it was useful I found that either it would slow down before I'd want to or speed up too quick into gaps or be very late on brakes. It basically never felt right.
Rented a Volvo XC60 in Sweden and it was totally different, did exactly what I expected and made the long drive we had much more relaxed. So I guess it depends on the car or how its implemented.
Personally I find a limiter far more useful than cruise control.
Final complaint is that it won't ever undertake someone which makes it useless in 50 mph road works where you are meant to stay in lane if someone is sat in lane 2/3 doing 40.