Tire wear on Continentals on RS????

Factory Continental tires were shot at 26K miles on the wife's 2021 RS. Went rounds with the dealer who always serviced it. They blamed needing an alignment. When I asked why his techs didn't point out the tire wear or alignment issue during the previous 2 services it became driver habit issues. Took it to another dealer and had new Goodyear Assurance all season 65k mile tire put on. They checked alignment and said that it was not off enough to cause the tire issues. Here we are 12K miles later and all 4 tires are shot. GM tells me pound salt it's not there problem. The dealer already lost me as a customer. Pretty sure this is either a Blazer issue or I got a turd GM won't stand behind. The last 7 new cars have been GM. Looks like it's time to move on to a new brand that stands behind their product.