"~10 pets" might've been an estimate we threw out a long time ago, and probably shouldn't be considered that much of a guideline anymore! It could still very well land around that number, but it's not something we've set in stone so to speak
Since getting all the pets in the game is optional, and getting at least one pet should be doable by everyone, we feel the stray from the game's core mechanics to be acceptable. The same goes for fishing, which is also a minigame of its own! A proper "wall" would be an infernally difficult story boss, while I feel this is more of a tree that's ruining the view from your virtual porch, and you really want to cut it down but since it's made out of wooden titanium you can't. Yes, that's an analogy I'm going to patent.
Some potentially good news for
@Varil is that we've been discussing pet capturing methods that don't involve the DDR-minigame, so you might be able to get some without encountering your rythm based nemesis!