I'm going to argue with the terms of the question, and suggest revising it to, how far is emotional intelligence innate or learned? Then, I would say, for NTs there's a kind of template already there at birth, which builds quickly through interactions and developmental progress.
For NDs, not so much. The template didn't get made because our brains did something else instead. Maybe they branched along and down, turned half right, ignoring a red light, then turned left and left again. Or any of many significant diversions. Now we can really think outside the box, but as for templates, what template? And who or what is that looming towards me through the mist? I'm gonna ignore it...
That's kind of how I think of it. Here's my crackpot* theory:
Our brains have hard-wired neural pathways for performing dedicated tasks like processing sensory input, reflexive reactions, emotional processing, basic social interactions, etc. It's all the routine things we do automatically, without thinking - the things we do
subconsciously. When something can be reduced to routine rules and actions and done subconsciously, the neural pathways to do it can become very efficient and optimized.
For things that can't be reduced to routine, we have
conscious thought. Conscious thought is not as fast as subconscious thought, because our conscious thought neural pathways don't specialize in any one thing. It's the catch-all, jack-of-all-trades-master-of-none part of the brain. But it's capable of thinking through and analyzing anything that is new and not routine.
For NT's, there are
subconscious, hard-wired neural pathways for feeling and managing emotions. They do it naturally and subconsciously. For ND's, those pathways either don't exist or are repurposed for some other use**, so we have to process them
consciously. That means we have to work out the rules manually and consciously process and manage emotions that NT's do without thinking.
*I call it a "crackpot" theory because it's just my own opinion without any scientific rigor behind it. It may be right, but it hasn't been studied, proven, or disproven.
**I suspect that some of my innate math talents and other intellectual talents come from re-purposing neural pathways that were supposed to do something else. I have to consciously work to do things that NT's do naturally, like social interactions and managing emotions, but I can do other things effortlessly that most people have to work hard at. I also think that once neural pathways go down the ND route, it's a crapshoot - you might wind up with neural pathways doing something useful, and you might not.