There are things I don’t “like” (like ridiculous coats or a stupid adherence to a silhouette, whether by coat or body shape), and then there are things which inhibit the dog’s quality of life.
ALL dogs, I’m sure you agree, deserve to be able to breathe, eat, walk, run, jump, mate and give birth unhindered.
The breeders of the more “questionable” breeds don’t see it that way.
If a vet or judge says “this basset has way too long ears, it’s practically stumbling over them”, the breeder might laugh and say “But it’s not a dog, it’s a basset hound! It’s supposed to be that way!”
Or an English or French bulldog, “this dog snores and heaves its head up and down even while sitting down, it’s not breathing normally”. “But it’s normal for a BULLDOG!”
That’s really messed up. They see their dogs as X breed or “my work of art/hobby” first, a living thing and Canis l. familiaris, second.
I can’t name all the breeds, but while there are obvious candidates with really messed up physiques (the English bulldog being the worst, everything from nose to tail is messed up on them), there are other breeds with sound confirmation, but which are wrecked by genetic illnesses (like cancer, heart disease, thyroids, kidneys, you name it), and they of course come from long-term inbreeding.
I don’t think we should necessarily end any breed, but the ones with internal illnesses need new blood (look up LUA Dalmatians for example, it’s an interesting story), and the ones with messed up bodies simply need to be bred differently, like those Frenchies with longer noses and legs, or Shar pei with less wrinkles, or German shepherds with straight backs.
TL;DR: If the dog is likely to be in pain (or hindered in breathing/eating/walking/running/jumping/reproducing) or become sick and die prematurely because of how it was bred, it’s unethical.
I did write-ups for 90 or so of the common breeds here, with the problems seen commonly in vet practice in Australia. They’re not complete rundowns of everything, but a decent introduction to the more common breeds here.