Kindness may not be natural to us. In 2018, it doesn't seem like it. Some people just seem awful awful awful.
Morgan Neville's WON'T YOU BE MY NEIGHBOR? makes a strong case for altruism as a learned trait. It takes ~effort~ to be nice. Fred Rogers expended so much energy being good in all facets of his life, which is almost impossible to conceive. All the people in his life existed in awe of him, as he really is/was an anomaly.
There's a couple of neat moments where the film questions the personal politics of Fred Rogers, modernizing a lot of his views and posing some very pertinent questions about his WASPish upbringing. I had no idea he was a Republican and an Evangelical pastor, two very scary character traits in our current world. And the film realizes that and works around it quite a bit.