The color of skin is no more relevant to anything than color of hair. You can know the percentage of, say, red-haired people in your country, but what for? The only thing where that could be needed is to fight e.g. some Dark Ages prejudices against red-haired people, and this is expected to be a marginal issue, not some all-encompassing national program.
The same goes for religion. In Europe, religion is inherently private endeavour.
There are, of course, race-motivated crimes, as well as, say, anti-Semitism. However, if some newspaper suddenly started publishing something along the lines of "in northern Paris, there are now more than 4.8% Jewish residents, an increase of 0.3% compared to the last year", the Jews would be offended, and rightfully so (perhaps not so much in the US, but definitely in Europe).
There is no need for public knowledge for racial or "country of origin" statistics. There is no need to specifically hide or distort this information, of course, but it is of interest only for law enforcers. Anybody else who asks for it usually have questionable motivations.
The color of skin is no more relevant to anything than color of hair. You can know the percentage of, say, red-haired people in your country, but what for? The only thing where that could be needed is to fight e.g. some Dark Ages prejudices against red-haired people, and this is expected to be a marginal issue, not some all-encompassing national program.
The same goes for religion. In Europe, religion is inherently private endeavour.