Too much is being made of this (which btw is great for Clark and WNBA ratings). People should watch the replay.
It was a frustration foul (Clark had just stolen the ball from Chennedy Carter on the previous play). Carter hip-checked her at the next in-bounds, Clark fell (you could say flopped) but in any case it was not a hard hit. It wasn't nearly as bad as, say, grabbing someone from behind on a layup and bringing them to the floor.
Refs called a foul (giving Clark a free throw that won the game), should have called a technical, that was the only mistake.
If you watch pro basketball, it is physical. Clark knows this. She is as physical as anybody but she cries to the refs every time she gets touched -- reminds me of Danny Ainge. It's just her style -- she's hypercompetitive, seeks every advantage she can get, it's what makes her the player she is.
So she won't get every call as a rookie. Neither did Larry Bird. But by Bird's second season, and for the rest of his career, he got the calls, and so will she. The sooner she stops whining on the court, the sooner she'll get the calls. This is called basketball.