[jiggy2011]

You can only measure repositories if you have "official" repositories which everybody goes to in order to get content. This would require strong IP laws to enforce.

What happens if a lot of stuff gets distributed P2P or via an independent repo who don't want to hand their server logs to the gov?

Also medical research still has contentious issues like Stem Cell research etc. And it is easier to justify objectively like "will help X thousand cancer patients".

Creative works are more difficult, for example what if somebody wants to make a film that might be perceived to promote racist views? There are certainly people who would not want their tax money spent on that.

There would also be people who would see it as an affront to free speech for such a film to not have a fair chance of being made.