Didn't you change your driving style between before and after? Because 22,000 km in 18 months on Primacy 4s isn't exactly huge to already have really visible wear. Primacy 4s are standard road tires and honestly, they hold up pretty well compared to others. Still, "quite a bit of wear" is relative - you really need to check the tread depth with a gauge to know if it's normal or not.
There are several things that can affect tire lifespan. Tire pressure first - if you're driving slightly underinflated, it wears way faster. Same thing if your wheel alignment is off, it eats through the sidewalls quickly. The 3008 isn't too heavy, but if you often carry a full load or drive a lot in the city with hard braking, obviously that wears them more than steady cruising at a stable speed.
As for Primacy 4s in general, you hear about tires that last well, but it really depends on how you use them. If after 18 months you genuinely feel they're done for, I'd advise you to check your wheel alignment and tire pressure before drawing conclusions. But honestly, even if you had to replace them at 35-40,000 km instead of 60,000, that's not crazy for this type of tire and this kind of usage.