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This is true.

https://en.wikipedia.org/wiki/Solar_power_at_the_White_House...

It is also true that solar water heating has unpleasant failure modes.

From a purely efficiency standpoint, yes, but practically, electricity->heat is a lot cheaper to install. Plumbing is messy, and bolting on a water circulation system to a roof is harder than delivering more joules over the wires.

Having gone through one ice-dam related roof leak in the past, I'm also not thrilled with the idea of superheated liquids hanging out casually above my bedroom while I sleep.

If it powers a heat pump water heater, it's pretty efficient, and much less plumbing involved.