I haven't made an argument for why the ones I've listed are actually crank subjects; I consider those granted and I'm not particularly interested in justifying them.
What I take issue with is the lack of symmetry. For every COVID denialist, you have a zero-COVID enthusiast. For every election denialist, you have an impending climate catastrophe doommonger. For every great reset conspiracy theorist, you have someone who believes we live in a meritocracy. Each of the latter positions is as merituous as their counterpart, but the former are treated with a disproportionate contempt.
I think symmetry in this case would amount to false balance. Why even bother to frame things this way? It's self evident to most people that crank views run the gamut of social and political backgrounds; like all things in life, we prioritize our discussion of them by their perceived impact(s) on our lives. COVID denialism has more of an impact on my life than an anti-nuclear crank does.
To put it another way: a lot of religious (particularly Christian) views amount to metaphysical claims that we can't really falsify. That's maybe sufficient to make them "irrational" in a narrow analytical sense, but insufficient to label them as crank-ish.