I mean, technology is probably not going to make rich people's lives better at this point unless it removes some substantial annoyance. I suspect that like money, there's diminishing returns after a certain point.
But, for someone who has never had internet before, to get connected (one of Mark's three stated goals in the video) is life changing.
Edit: By the way, this is the essential difference between Bentham's and Mill's versions of utilitarian philosophy, if you'd like to research further. https://en.wikipedia.org/wiki/John_Stuart_Mill#Utilitarianis...
You can read about humans, to understand humans you have to form relationships with them and experience them yourself. An analogy would be reading K&R compared to bashing against GCC.
See e.g. http://nautil.us/issue/31/stress/is-facebook-luring-you-into...