I never met Carl Sagan but in addition to being a good scientist, prolific writer, great popularizer and advocate for science, he had the reputation of being a really nice person, which is probably why so many of us mean and nasty new atheists are urged to be more like him.
Neil deGrasse Tyson relates an anecdote that reinforces that last characteristic.
The true character of a person is revealed in the way they treat people who, by the usual standards of society, are of no importance to them whatsoever.