You're gesturing at an unconvincing objection: that there is no difference between reflection and emission because there is a sense in which light passing throu

You're gesturing at an unconvincing objection: that there is no difference between reflection and emission because there is a sense in which light passing through matter is continuously being absorbed and re-emitted. (I say "gesturing" because you don't actually know the physics; it is completely different than either stimulated emission or the photoelectric effect, which you could tell by reading the Wikipedia articles.) Explaining why this objection is boring and unconvincing would ultimately be a long discussion in the philosophy of science ("how can we keep using folk terminology that presumes a sharp devision between two concepts when a theory of physics suggests they are actually just part of a continuum?"), but you can get a sense of that by noticing that emission generally involves a change in the frequency of light while reflection does not.