Doesn't this make you feel like a mushroom?

I didn't claim "that this was only made possible by cutting back on UV shielding." Those are your words. Though it certainly seems plausible that that is at least a portion of the tradeoff.

As a tradeoff, I am gaining enormously from the greatly increased tread life, and losing nothing to the reduced UV protection, as my tires still get scrapped for tread loss before UV degradation becomes an issue.

 

so, drive without tyres, or don't drive at all? seems like rocket science to me

 

Not knowing carbon Tire compounds from Shinola, went and did a Grok search real quick. AI seems to think virtually same amounts of carbon are used on the tire side walls - where it's most likely to be affected by UV & it's primarily the tread that gets the fancy schmancy compounds that increase traction, improved rolling resistance Etc. Besides, average driving equaling 12,000 Mi a year means tires are pretty much getting ready to be replaced at the ½ decade mark anyway.

 

what tyres are you running?