Current coverage is
Even though the population percents may be informative, I have the feeling that it will become outdated very quickly. Therefore, unless we can keep up with the bi-yearly CLDR release schedule, we may be left behind again (like when we supported CLDR 23) and, then, such data will not be very useful.
On the other hand, the supported languages by territory will hopefully change in a less dramatic way.
One solution could be to add a big fat disclaimer note regarding the possible lack of accuracy for the population percent information.