The dominant way SC has played this year? They have played three ranked teams, two of them single digit wins, one of them in over time and the one that wasn't close, Maryland, was playing without their best player. If they were to lose to an undermanned and depleted UConn team I don't think they have a strong case for the number 1 overall seed objectively.
Now, I do think South Carolina is better than UConn and will win out over the weekend by a large margin. So I do think they WILL be the overall number one seed. BUT I think if things don't go as we all expect them to over the weekend UConn would actually have a stronger resume going into the tournament than maybe you realize.