I see this exact line of thought in the other direction: both Republican/Democrat parties are left wing because they both support white genocide etc. And they do. So that take has more merit than the take that both Republican/Democrat parties are right wing.
Name one truly right wing policy of the Democrats. For it to qualify as truly right wing in the context of America, it needs to act as a countervailing policy to their decidedly left wing view that straight white men need to be replaced by black transbians. You can’t.