Vox has a long article by P.R. Lockhart here. As an anti-tribal non-identarian myself, I personally have no interest in supporting the identarian group aims of anyone; but I am concerned about the principles underneath this regarding the credibility and objectivity of public speech.
Facebook says it had wanted to consider ideas like patriotism and nationalism as legitimate; but given US history, it could not do that with “white” issues specifically, given partly the history of privilege in the past, and the constant connection to probably unlawful “groups” (and incidents like OKC, Atlanta (1996), Charleston SC, and Christchurch). That position would seem to apply to Europe, where in some countries the problem (with respect to separatism) sounds similar (consider Poland, Hungary, “soft fascism”). It is also a big controversy in Russia among the former republics. The comparison to Zionism in Israel is said to be a canard.