I believe in shleimus ha’am – and that means keeping erev rav and goyim mechutz lamachaneh. Insincere converts convert for their own gain, and they do not contribute a thing to am Yisroel. We have enough problems as it is – we don’t need new ones who are descended from Cossacks and Eastern European peasants who tormented our ancestors.
I lived among these con artists. I have provable stories of their post-geirus behavior that involve issurei skila and worse. (They are not fit to discuss here.)
We don’t need this kind of trash in our midst, or in our gene pool.