So, if your source of random data does not reduce entropy to the pool, but generating random numbers with it does reduce entropy from the pool, along a long enough time line, aren't you going to deplete the entropy anyways?
The Linux random number generator did used to have a notion of entropy depletion, but that is no longer the case (at least for x86-64 systems: https://wiki.archlinux.org/title/Random_number_generation).
On older systems that have a notion of entropy depletion, you would eventually deplete the entropy counter and /dev/random would start blocking if you aren't feeding new entropy into the system.