The laughably ironic part of all this is that right-conservatives inevitably end up curators of the past hard-won victories of the liberal-progressive left...
It's true that there is a lot of this, but I don't think we should assume that this is or will always be the case, or overstate the significance of the case as it plays out.
The Right is essentially anti-democratic, it is a reaction against democratizing forces in history. It is literally reactionary, right?
Of course, this is because the Right is essentially the politics of incumbency, an expression of the prejudices and parochial interests of established elites and customary attitudes, the positions, privileges, and institutions that are most threatened by democratic educational, agitational, and organization forces abroad in history.
Sometimes, incumbency serves outcomes achieved by particular vicissitudes in a longer struggle of democratization, as you say, but don't get seduced into a hasty overgeneralization or obfuscatory metanarrative here!
One needs to look at the concrete interests of incumbents as they themselves testify to these to know exactly what the Right will fight and fight for in its contemporary service to incumbency and ongoing struggle against democratization.
We've just lived through a weird generation throughout which, at least in key ways, actually progressive democratizing forces were "conservatively" defending partial accomplishments of the New Deal and Great Society against the "revolutionary" fervor of radical anti-democratic elitists peddling market fundamentalist ideology backed by US military might.