The range only needs to cover the period between mandated brakes. Everything over that is wasted weight, as the weight of the cargo and the weight of the truck share a weight budget.
Trucks/lorries drive lots of places other than UK motorways, and they are not doing 60mph down the A4.
I was confused there for a second until I realized you meant "breaks."
So it almost seems optimised for the mandated break timing.
On average truck journeys in europe are only 72 miles anyway so...
That’s astonishing. I’d be curious to see the median and mode distances compared between the U.S. and E.U.