I find this exchange to be quite fascinating — in late 2017, I wrote a series of blog articles in which I tried to enact a sort of a confrontation between your “realism about legitimacy” and my own prior reliance on a Habermasian/Rawlsian “ethics first” set of assumptions about democratic legitimacy. The articles are linked, and here is the first one: https://www.indarktimes.com/rethinking-democratic-legitimacy/