By rule definition, a flagrant foul includes an "'intentional foul' of fouling an opposing player to prevent an easy breakaway score." Saunders did that. Even Pope afterward said that was an obvious F1.
To clarify, it was NOT a F1 because of "excessive or severe contact."
And, yes, the Baylor player definitely over reacted in an effort to sell the call, but the F1 had already been called.