No, you were clear the first time, but that’s not how it works. When that is done it becomes a new drug, not a generic version.
It’s pretty reasonable what he wrote tbh. That is kind of how it works, and the thing about incomplete chiral purification possibly accounting for some of the differences between manufacturers is plausible in principle. It’s more of a dosage/formulation issue than a “different drug” issue, since the API is identical in both cases.