Tyre wear is proportional to the fourth power of wheel load; reducing weight per wheel is the key here.

No, it's not.

You're taking a very loose rule of thumb for road surface wear and baselessly applying it to tires.

Tire wear follows the rubber the tire is made out of. Soft rubber wears faster. Once you control for that it's acceleration and braking loads (i.e. driving style) that dominate. After that is when weight starts mattering.

If what you said was even remotely true then heavy vehicles would get obviously less life out of tires compared to compact cars when in reality they get about the same

> If what you said was even remotely true then heavy vehicles would get obviously less life out of tires compared to compact cars when in reality they get about the same

Are you assuming that the tires of heavy vehicles have the same thickness as lighter vehicles? My bike has much thinner tires than any car, and they can last ten thousand kilometers.

I'm not sure where you're getting these ideas from. Best estimate I can see of prime mover tyre lifespan is 40,000-120,000 km.

I'd be quite happy if I could get that kind of lifespan out of my cars tyres.