So, I have been going to Tesla to service my car regularly (fixing a rattle in back that still persists, replacing a corrupt MicroSD card, fixing a loose dashboard, alignment) and they just told me on my last visit that my tires were down to 3/32.
The PSAs here are that a) Michelin treadwear warranties do not apply to OEM tires 2) Tesla will not cover the tires under the treadwear warranty 3) call Michelin directly to see if they can help 4) if you get aftermarket tires, make sure you rotate them (and get receipts) every 6,000-8,000 miles.
After a couple of calls to Michelin, getting friendly people to help, and going to a local authorized Michelin retailer, I was able to get my tires covered at 50%.
I learned that OEM tires are generally made with inferior rubber than the exact same aftermarket tires, so OEM tires generally last much shorter than rated.
I had considered the Michelin CrossClimate+ as a replacement and my tire shop warned me they would be super-loud with the tread that looks similar to the discontinued Goodyear Aquatred. I am going with Michelin Premier A/S tires as recommended by the retailer. He said it was the best balance of performance handling, noise and treadwear. He said the Primacy MXM4 were sh*t tires. Given he is not making money of the sales of the new ones and is recommending cheaper tires, I have to believe he is being honest. Neither was in stock.
I have a M3 LR DM.