^You know, never did, although I’d heard of it, until moving to western WA.
The snow here is super wet and thus it’s far more slippery than colder climates. It’s basically wet ice in the mountains as soon as it gets driven on.
Started doing it on mud tires because they don’t have any or few factory sipes.
But it even helps on AT or HT treads. Same concept as snow tires.
Generally the trucks that run over the passes in the winter, I sipe the tires.
Difference is night and day on mudders and it makes them not only good in deep/loose snow, with the big open lugs but helps the lugs grip the slippery stuff as well.
On AT tires which are like good at most conditions but not the best at anything, it’s also a noticeable improvement.
On any tires, especially heavier trucks, I don’t have them siped all the way out to the edges. That serves to wear out the shoulder treads much quicker. Just the inner tread rows and maybe halfway into the outer rows.
Depending how how drive and tire compound, it “can” decrease tire life, but on some tires I’ve seen as good as could possibly be expected so I don’t think it generally accelerates tread wear.
Also better traction dry and rain but not as pronounced as on snow.
Current personal rig has 37” mudders, not siped, and pulling the snowmobile trailer last week, even with nice low tire pressures on the truck, it got markedly worse traction than siped.