I have had similar observations about chaotic driving, people are cautious. At place where I live in India at present, one can actually cross roads walking slowly ( The traffic will just go around you )

I do not think there's much truth in "No side mirrors" argument though, I have seen some very old trucks and buses here in India, and cannot recall any missing mirrors.

Infact, the general convention in India for overtaking a truck is to flash highbeam light, turn on the indicator to highlight the edge of your car and overtake.