If we think of the many worlds interpretation, how many universes will we be making every time we assign a CCUID to something?

> many worlds interpretation

These are only namespaces. Many worlds can have all the same (many) random numbers and they will never conflict with each other!

In that interpretation the total number of worlds does not change.

We don't "make" universes in the MWI. The universal wavefunction evolves to include all reachable quantum states. It's deterministic, because it encompasses all allowed possibilities.