There are several varieties of carp including one species of 1/2 skin, 1/2 scale. . . nasty. They are an import from Europe in the 1800's for food and sport. When the carp is feeding in clear lakes or rivers, they might taste clean, but in most of our lakes they feed by sucking up the mud and gunk, and that's what they taste like.
Carp are considered trash fish, because they hurt the fishing for all other species. A 10 or 20 or 30 pound carp will push other fish off the nest and eat the eggs of sport fish. Also, after bass eggs hatch, the male bass will lead the fry around for a while. . . I've watched carp hunt and eat entire spawns in front of the smaller bass.
In years past a good spearfishing tournament in Texas or Oklahoma, might have 200 divers and bring in 300 or more carp. Anyone that wanted fish could have as many as they wanted. Unclaimed carp, we would haul off to a hog pen. . . hogs didn't care about the taste, just the feast. When these spearfishing tournaments went to swamps in the winter. . . we would bring back hundreds of Gar. Locals would stand in line for free gar.