Question about Apple Thunderbolt 3 zu

A thumbs up from me, too. The adapter does not offer video transmission, although the input socket is similar to a Mini DisplayPort plug. However, data transfer works perfectly and reliably. The adapter is designed to operate older devices with Thunderbolt 1 or 2 interfaces (uses Thunderbolt connector) on new Macs with Thunderbolt 3 or 4 interfaces (uses USB-C connector).

Your Focusrite Clarett seems to have a normal USB-C connection, so this adapter will probably not be necessary. A normal USB-C cable should suffice.

I bought it with the same intensity for video (2017 iMac) and it works.
8-tung: first the operating system must be of a newer generation.