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?
Randomness from a CSPRNG (cryptographically-secure random number generator) never really gets "depleted," since as long as the seed contains enough entropy and isn't compromised, then it's computationally infeasible to learn anything about the internal state of the CSPRNG from it's outputs. See https://research.nccgroup.com/2019/12/19/on-linuxs-random-nu... for a nice overview.
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.
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.