I was trying out the new 1.20 beta to find suspicious sand, but the pyramid I found was underground. I couldn't find any sand or suspicious sand near the desert temple. If the desert temples are supposed to spawn underground, shouldn't there be sand?
Environment
Java edition, snapshot 23w07a, 1.20 beta, MacOS
Does Panda's comment answer your issue? If not, please type the world seed and coordinates.