Like most things, it would depend on what you wanted in a pet. Some people want a pet that will shut up. Other just want something to talk to. Others just want a miniature horse.
brown probably wouldn’t be as undesirable a color as people seem to think. sure, little girls won’t like it, but adult fluffy collectors would see neutral colors like grey and brown as more fashionable than eye-melting magenta with neon purple accents.
having said that, not every shade of grey and brown are considered nice colors, and only natural tones are considered a nice accent color to go with. people looking for nice natural tone fluffies would look up a breeder that specializes in them so they can be certain to get a foal they actually like. breeders and ferals that produce brown and grey foals by accident will almost certainly produce a foal that EVERYONE would consider ugly.
so, i think there would be two separate markets with two separate goals. one is for children, that favors bright crayola colors and playfulness, and one is for adults, who favor natural tones and more demure, reserved behavior…
…and they DON’T mix. breeders looking for natural tones will violently dispose of and punish the mothers of “vomit” fluffies, and breeders looking for child-color fluffies will violently dispose of and punish the mothers of “poopy” fluffies.
woe be to any fluffy that doesn’t perfectly fit into either group and can’t understand why the humans contradict themselves when judging its colors.
one day one of each breeder type get together for a meeting and both end up killing the other’s prize stud after mistaking it for a stray based on color.
in my mind’s eye i don’t think they would be that expensive with how fast you can breed them so you can keep selectively breeding the ones with good colors while throwing the ugly shit ones into the mouth of a very hungry pitbull
I think the wilder colors would sell better. Plus, most of the chatacters on the show have manes and tails that are different colors from the main body.
Also, they seem to be mostly mammalian. You can find black, white, and brown horses, cats, and dogs all over the place. But with a fluffy, you have a full rainbow of options. I think people would be happy to take advantage of that.