The Minotaur just had a bull’s head, and sometimes a tail. Everything else was human. We usually imagine the shoulders as broad and bull-like too but the Greeks just went with bull’s head (and sometimes tail, but just the tail, like when anime furries make cat girls. Yes I said it)
I would say the image OP meant a centaur and not a minotaur. But then the other way around would be a hippocampus!
No they’re saying the human half of a minotaur (from the waist down) and the human half of a merfolk (from the waist up).
Centaurs don’t have horse heads, so they can’t make a water horse.
The issue is that the bottom half of a minotaur is just the hind quarters of a bull. But you are right that centaurs miss the horse head too
The Minotaur just had a bull’s head, and sometimes a tail. Everything else was human. We usually imagine the shoulders as broad and bull-like too but the Greeks just went with bull’s head (and sometimes tail, but just the tail, like when anime furries make cat girls. Yes I said it)
https://www.greekmyths-greekmythology.com/wp-content/uploads/2009/08/theseus-minotaur.jpg
https://avradio.sgp1.digitaloceanspaces.com/wpcontent/uploads/import/2018_04_18_performance_the_minotaur_and_the_labyrinth_satyamayi_english_2.jpg