Can Thunderbolt 3 cables (passive or active) be used in place of Thunderbolt 4 cables?

No, the cable Thunderbolt version should match the peripheral Thunderbolt version, since using a mismatched version of Thunderbolt cable can cause unexpected functionality issues. When connecting a Thunderbolt 4 peripheral such as the TB4CDOCK, we recommend only using a Thunderbolt 4 cable, especially if also using a Thunderbolt 4 host device.