UConn lost to two teams sub-.500. That has to matter.
Three of those 7 losses were UConn, Duke, Arizona, all close games. And their worst loss was to a bubble Auburn.
They got a good SEC draw, not playing the other good teams twice, and they racked up wins well. In retrospect, it seems clear to me they were overrated, and probably more of a 3-seed than a 1, but (a) there are other teams that didn't do what they could have, and (b), UConn didn't deserve a 1-seed with two losses to sub-.500 teams AND 3-seed advanced metrics.