I think anyone can learn the math/odds part of poker, and probably anyone can learn to read betting patterns if he is paying attention, and plays enough.

What I think not everyone can learn is the kind of emotional stability you need...always playing your best game, always staying focused, not starting to tilt.

So the technical side, yes I think anyone can learn it. The emotional side, selfcontrol, dedication, confidence in your game, I think some people cant learn.