But his argument isn't that there's no other ways to signal an ideological commitment. In fact, he's argued quite the opposite with respect to voting. His point is that the substantive outcomes that are described as linked to equality and egalitarianism, as opposed to "poverty" or "extreme inequality" (note the distinction between what he's referencing and what your turns of phrase may mean) are not ones for which we have clear behavioral evidence that people care.

It's not as if people are not …

Most people deeply crave inequality. They want a better partner than the median partner. They want to make more money than the average by getting a promotion their competition did not, playing office politics to climb the greasy pole faster than other contestants. They want their kids to go to the most exclusive universities. They want a home in an upscale neighborhood. They crave to vacation where others don't get to, exclusive restaurants in exotic lands that they can signal about on their so…

I take your point.

That said, Equality with a capital “E” is impossible. So to me it’s testing for something that’s theoretical. It’s hard to care about something like that.