Why are people so selfish?

I don’t know why this is such a big deal, but it is. How much time does a motorist lose by having to pass a cyclist? 10 secs? 30 secs? Can that time be made up? Is that time essentially negated because you’re going to get stopped at the light anyway?
People are in such a hurry to do everything these days that they are the ones that put people at risk, they are the ones that endanger cyclists, runners, walkers anyone on the side of the road trying to improve their health.
On the other side of the coin, why must cyclists antagonize the already upset motorist? People that ride two abreast on a 2-lane road are giving cyclist a bad name. They’re doing it in the name of sharing the road, but is that really sharing the road.
Don’t be in such a hurry and be considerate of others. Why is that so hard?