Thanks, didn't know this - but from my experience, DMT smoke smelled and tasted kind of plasticky (like when you burn plastic). Did I just interpret the poop-smell differently?
So it's not so much that it smells like poop, just is as revolting in some more general sense. And DMT probably has a lot of bitterness to it(can't remember what it tastes like, honestly, but I remember its cousins AMT and DPT being intensely bitter, though I didn't vape them).
Weirdly, skatole also smells nice in very small quantities, and is apparently used in perfume.
So yeah, odour is a pretty strange sense...