“Truck driving licence” is rather simplifying it.

There are carious degrees of licences between B (up to 3500kg) and a “proper” truck driving licence, CE, which allows you to operate actual full combination trucks.

C1, one above B is basically a van licence, and that’s up to 7500 kg and up to eight people. This is a fairly common licence.

I myself have a C licence, which was also very common to drive when I went through driving school, and it has no weight limit. I can drive a truck of any size, but I don’t have an “actual truck licence” in the sense that I don’t have the CE licence nor do I have the professional licence for a C sized truck. (And I can’t drive buses, those call for a D licence instead)

So basically something that exceeds 3500kg but isn’t a professional vehicle is the only thing my C would be useful for. B class licence is certainly more common, but C and especially C1 are still plenty common.