As far as politics today is concerned, I would sure hope that both conservatives and liberals both agree that is it wrong to deny service based on someone's membership in a protected class.

Of course, as a progressive (I'm guessing), you would hope the overton window stays firmly within the progressive comfort zone. This has little to do with the fact that progressive laws do, in fact, generally work in opposition to conservative (rightist and/or libertarian) politics, even if we can retroactively come up with some clean-sounding justification like "it's about human rights". It's not self-selection bias.