Forget golems, we have amoraim making calves out of nothing! The gemara says two of the amoraim would make calves for their dhabbos meals using sefer yetzirah.
Is everything a mashal because you can’t find a scientific explanation of it? When the rambam dismisses magic and demons, he doesn’t say that they’re not true because they’re not scientifically provable; he says they’re just narrishkeit.
Whereas he accepts the existence of angels, and nowhere does he object to the created calves or golems described in chazal. Nor does he reject the Salamandria or other wonderous animals with seemingly supernatural powers.