Maybe it's my lack of understanding, so correct me if wrong, but I believe biological systems complete emulation are not yet a solved problem. You can approximate, omit variables, deal with error correction, and, at best, model it in a way that extrapolates it but you cannot confidently assert.

There's so little we know about biological systems despite much of the advancements, it's sort of pretentious to say we should give up on them because we can scale digital systems.