I agree but I also they think don't get her in a multitude of ways- for a big like her, you can -
1. Catch her rolling to basket off a screen
2. Get her Iso'd on the block off an inverted wing with your best three-point shooters
3. Do a pass, repass, post and repost (which they tried)
4. Do set plays where 3 point shooters shoot intentionally and allow her to offensive rebound.
Close has restricted her to the paint and if she is she needs to Monica Czinano her and tell her not to dribble because she travelled everytime she felt pressure against USC. You either do one or the other. But I think using her as a decoy was better, she is a terrific passer.
Regarding Betts, you will notice that Betts will (1) roll off the screen, but will rarely get the pass in motion. 2 and 3 will happen quite a lot. 4 doesn't happen enough, possibly to create space for a shooter by clearing space close to the basket for the threat of a drive to cause the defender to sag off the shooter.
Frankly, Betts, though improving, doesn't have the best (biggest?) hands. She's perfectly capable of making a good target and catching a pass from a static position, but handling something in transition (from high to low post, or cutting diagonally) is much more of a crapshoot. She's clearly gotten better at this over her career, and, as you mentioned, her passing can also be impressive.
In this game, USC had three competent post players to burn fouls with, along with assorted other players, and were clearly trying to frustrate her with physical defense. This clearly was effective. Subjectively, the refs called quite a lot of these fouls early in the game, causing a sizable foul differential in UCLA's favor, but started to ignore some of the physical post play when it might have seemed like they (the refs) were going to decide the game. As well, UCLA started playing Betts in the high post later in the game, which opened the middle for drives but eliminated Betts from the offense.