Wow, interesting. Well, it doesn’t smell similar to poop to me (and presumably the whole chunk of people that like it).
It does have a characteristic smell/taste, but it’s much more in line with what you’d expect from green vegetables, similar to green beans or zucchini. It’s also not that far away from cauliflower or Brussels sprouts, but presumably those taste akin to poop to you, too.

And this is a personal epiphany, but my Dad would always say (in German) “Rosenkohl, Hosen voll!”, which basically translates to “Brussels sprouts, crapped pants!”.

Well, it rhymes in German, and Brussels sprouts do taste somewhat bitter to the non-poop folks, so I always thought, he’s just doing the Dad joke thing to express his dislike for that bitterness.
But yeah, I’m guessing, he was being a lot more literal, that it literally smelled to him like crapped pants. I’ve never seen him eat broccoli either. Cauliflower, I’m not sure…