This time on my current car the front tyres had to bechanged half way threw the 3 years(because of acc it braakes more than i would) normally it’s been in the last 6 months of 3rd year that they dropped below 2mm and i guess that is over the legal limit.. so acceptable.
Guess maybe the fact the road surface is a lot hotter in the summer than now, which has an effect on softer compound tyres wear, not just all about tread / type of tyre and i guess as has been said the car makers put on the tires that best overall for that car for most conditions to handle how they intended. but any tyre is not perfect in all conditions. so if you live up in the mountains it maybe a real problem but for most of us we not seen any snow this winter, or the gritters out much.. yep there been alot of rain but personally in 30 years of driving not had them and tyre tech has come along way from when i first started driving.. So i can see why it is the way it is… It would be worse if mb wouldn’t allow you to change the tyres at your own expense and also is it classed as a mod to the car, so insurance gotta be told, like changing size of the wheels.