Did you notice that they do not detail exactly what the state should do differently?
Is it really the state's job to ensure certain groupings receive a certain degree of representation? Wouldn't the "solutions" to this "problem" be thoroughly anti-democratic? What percentage of these people actually vote, isn't that their fault and not the state's? Perhaps the state could do more to encourage language proficiency and civic mindedness, that might be an obstacle to voting. Or perhaps there is an ideological obstacle that no government intervention could ever overcome...
The solution is certainly not quotas, but I don't think that is what is surprising and shocking is that there are no government imposed quotas. What is shocking is that France, which constantly declares its "social model" as superior to that of the US, can't even assimilate such a large percentage of the population such that they would participate in the elections or democratic institutions of the country.