It doesn't prove it. Khan attempted very fiercely to block Amazon's purchase of iRobot and she, along with the EU authorities, succeeded in preventing it and now iRobot is about to file bankruptcy. We don't have the counterfactual and founders (nor regulatory agencies) can see the future.

Someone made a good analogy on twitter that Khan essentially cut off a genius pianist's right hand, the pianist persevered and somehow succeeded in retaining their talent in spite of having one hand, and now Khan is taking credit for the feat. In the same way, the fact that Figma still exists is not proof that she was right.