While I agree that's a great dock, IIUC, it's not technically a USB-C dock, it's a Thunderbolt dock. I know it's the same cable but IIUC it's not USB-C?
USB-C is the connector type, so yes Thunderbolt 4 uses USB-C. The transport standard is USB-[some number], current gen being USB-4 (which is actually based on the TB3 standard).