However (and correct me if I am wrong), this seems to refer to empathic feelings in retrospect. Or, do you see people as 'shades' also whilst you are with them? Ps: I understand this is not judgmental.

Besides very few people I actually do. I simply cannot relate to most people in any way emotionally - yet alone feel emotional empathy towards them. Usually I'm more interested about raw information gathering about another person, because having more knowledge about someone/thing is always better.
But I immediately forget people's name after they tell me. I once lived together with two guys in a flat and it took me about half a year to figure out the name of the second guy - and only because my other flat mate called him once. So, yeah, I think "shades" describes it quite accurately.

I haven't come across any studies on neuropsychology suggesting the lack of emotional empathy might be inherited. But, if I may give my opinion, I believe this has more to do with learnt (or 'unlearnt') behaviour than inherited factors, as it was briefly discussed here too.

Maybe. I'm not sure about that. I think it's a combination of both. An inherited lack of empathy due to brain structure and epigenetic factors as well. I had always difficulties adjusting to social norms and feelings of others - it took me years to really learn how to behave adequately during social interactions.