Are there any good soccer data collections (free / reasonably priced) for an individual programmer to build something like this?
I have to assume computer vision will largely automate the process of collecting sports stats, even in real-time, if that hasn't already happened. For that I think you would need access (and licensing rights) to a quality video feed of the matches, different than what is broadcast for human consumption (i.e. shows the entire field of play the whole time).
Sure it would very noisy, but synchronised feeds from many angles seems valuable.
Lots of your local and state tax money for high school / university sports programs gets dumped into it