It was probably one of the easier exercises to monitor automatically, I should think a camera is less prone wear&tear than a pressure mat for planking... There is also hygiene to think about, not in the sense of an actual concern, but in the sense that people will be more averse to lying face down on a mat used by maybe hundreds of people every day.

I do agree with your sentiment BTW, here in Norway there's been quite a bit of talk about similar programs through the years, but there are just too many pit-falls on the way, usually doesn't even get past the "Rights for X" organisations' whining.