Literally JUST came to the forum with this same complaint! It’s nuts how I mine out hundreds of dirt blocks and get a handful of clay. It’s not so much that clay ‘drops’ less frequently it’s the logistics required to amass significant amounts to supply your industry.
It’s sooooooooooooooooooooooooo much easier felling trees for wood. They are easy to access without Hearthlings needing extra paths to access from different directions. One tree comes down super fast and drops a bunch of wood. I don’t have to deform huge swaths of the map or dork around with slice view. Eventually I have tree farms as a easy renewable wood source. It takes more Hearthlings to keep up a steady supply of clay than it does wood.
Playing RC is such a chore… a pity because I do love playing them.