The Model 3 is very close to the same weight as a BMW 3-series. It's not substantially heavier.
https://www.michelinman.com/auto/auto-tips-and-advice/electr...
Apparently it's not just the weight, it's the instantaneous torque and noise that need to be considered. Lower noise and higher torque tolerance would, to me, imply a softer rubber compound is used, which would reduce longevity.
On the other hand, they also mention range and rolling resistance, which suggest that a harder compound might be used. Harder rubber typically corresponds to better longevity.
It's an interesting topic. Has anyone done a proper apples-to-apples test of EV tires versus their nearest equivalent "normal" tires?