You assume he cares. Assuming the person across from you gives a crap about you is a regularly fatal one.
Humans are not basically good. They are basically greedy.
It's worth noting that they're not always opposing. Sometimes empathy makes us feel better when others feel good, and the negative impact on ourselves can be more than countered by the good feeling from making others happier.
It's more complex than that, albeit not much. If you are in a hurry skip to figure 3. https://www.science.org/doi/10.1126/sciadv.1600451
Also, psychos tend to concentrate in certain places. If you're in a board room, or hanging out with a bunch of surgeons, perhaps it's rational to assume everybody else there is a psycho.