The seat is comfortable, but I wish they had made the side bolsters a bit deeper. The design is a bit flat and doesn't hug you as well as it could. That said, it is still a comfortable seat for my taste. I think what you might be experiencing is fatigue from holding the seat on turns with your thighs. I do notice that when I make my turns in the Blazer. I'm comparing this seat to my 2016 Maxima SR I traded for the Blazer. The Maxima had some very well-designed seats and they were zero gravity. I had that car for 6 years and got spoiled with it. The only fix is to buy aftermarket seats that perform better. That's if you can find them for a Blazer.
Or, your thighs are defective, at which point, you may need to consult a doctor for that.