Blizzard’s WoW team leadership has always thought this way. Ghostcrawler has a famous quote that basically implies it’s not necessary to balance hunter pets because most players will choose the one they like the look of, whereas only a very small minority would be willing to tame an untextured cube for a 1% dps increase. As if the choice wouldn’t be made easier if all pets had the same damage and it was literally just a cosmetic choice.