Human babies are born knowing how to swim, I suppose they learn that in 3 seconds as well? Both of these are far more likely to just be genetic memory. If you can encode how to fold proteins to make wings, then packaging a control algorithm along is completely trivial in comparison.
As a baby I fell into a pool and needed to be rescued. I didn’t inhale water, but as generally happens I very much did just sank to the bottom. Babies can be taught to float at around 5 months, but it’s not reflexive.
I mean they kind of have to when they're part of a species that's curious enough that they'll hear 'babies can swim' and throw babies in a pool en masse to see if it is be true.
I can't say what the extent of those swimming reflexes really is, but water births are not unheard of. Besides there's literally countless examples of this sort of thing, most prey animals can walk or even run mere moments after being born, cetaceans and ram ventilator sharks all know how to swim immediately or they would literally drown, insects can fly as soon as they hatch, etc.
All good examples, but humans are relatively underdeveloped at birth compared to most mammals due to the necessity of limiting skull size to allow an easier birth. An infant cannot lift its own head or locomote for several months, for instance. Just like marsupials finish up outside the womb in a pouch, we have own external phase.