I commented something similar on the duplicate of this report, but I have the same issue, and the bug persisted when I generated a new world in the most recent snapshot with a different seed. I have yet to test it on the suspicious sand found in desert temples and wells, but the fact that it affects the sand and gravel in multiple trail ruins across multiple seeds and both snapshots makes me think it might have something to do with the new loot tables not registering properly.
-I also just noticed me and the original poster both have the most recent "show coordinates" data pack from Vanilla Tweaks on, and I don't think it would make a difference, but its just something to note if other people who don't use data packs are not having this problem.
I have the same issue- I was using a world generated in the previous snapshot, but I checked by creating a new world in 23w16a and had the same problem.
When looking at the loot table data, I noticed in the previous version that the single loot table file associated with suspicious sand had some loot assigned with a weight of 2 and some without. That is still the case with the common loot in the newest snapshot, but in the rare loot data, none of them have any weight numbers listed; I don't know if that matters at all, but maybe it has something to do with the rate of what loot if any drops when the sand/gravel is interacted with?