>>32825811>The games clearly state that they do though.Pokémon study is VERY much like the study of animals so this is not the case.
It's simply the professors labeling them as genderless because they've not been able to study them enough to verify what gender they are, in other words. Often due to them being legendary and thus rare.
Just like in X/Y it's implied Fairy-Types always existed but weren't classified that way until further study into Pokémon in general made it necessary.
You know, like when further testing of an animal will reveal it's actually a different species than we'd thought.
It's called the Undiscovered Egg Group, and not the impossible to have eggs group for a reason. Their simply classified as genderless until further study (which from a gameplay perspective will likely never happen).
