The stats you quote are inaccurate. She's 37% from 3 and 54% from 2. For comparison, the highly praised Lou Lopez Senechal is 48% from 2, 47% from 3, and Siegrist is 56% from 2 and 39% from 3. Clark has extremely good numbers.
I do agree she's more efficient when she takes the ball to the basket or pulls up from mid range. When she shoots midrange in rhythm, it's automatic. And she's a great finisher at the basket. What makes her so dangerous is she can knock down 3s from anywhere within half court, beat you off the dribble and is darn good at scoring from mid range and at the basket. If I'm a coach and have a limited supporting cast like Iowa does, I have absolutely no problem with her taking that many shots. Last night she missed a couple of layups/close range shots she normally hits, and I noticed after her collision with Moore-McNeil, she was short on a couple of 3 pointers when CMM closed out on her. It looked like she wasn't as focused/confident on those shots so I'm guessing the collision probably affected her focus.
The problem for Iowa is they effectively have 2 reliable options offensively in Clark/Czinano, and if Czinano is off they're quite beatable. Looking at the rest of the team, Warnock is a great role player in that she hits her open looks, rebounds and does her job well, but she isn't someone who takes a lot of shots or creates looks. She's never shown ability to be a go-to player or someone who will regularly take 10+ shots a game. When you watch her play you remember a shot or 2 going in and then look at the box score and are surprised to see she has a great statline. Gabby Marshall is a solid defender but offers very little offensively aside from knocking down open triples, which she has struggled with this season (30% FG, 25% from 3). Kate Martin similarly doesn't offer much offensively aside from being a 3 point threat and completing open looks or layups, often created by Clark. It's a limited roster and often times Clark taking 20+ shots is the team's best option.