>>56846295In a game like this I think it's fine. They have very rough catch rates, and certainly aren't just letting it happen. Your odds of actually catching them, assuming you're not duping balls, are pretty reasonably low, unless you build specifically to do it, in which case... that build choice is rewarded.
It's like blanket banning legendaries in nuzlockes. It's a coward's approach, actually trying to catch legendaries in nuzlockes is actually pretty dangerous, almost always results in dead pokemon, and isn't even guaranteed to pay off, if you run out of balls or it struggles/recoils to death.