Laws should protect the common interests of the people and should not be beholden to powerful institutions that act in direct opposition to the welfare of the people. This shouldn't need to be explained further.

The oppositional force here is probably gravity, we can't detect the graviton because it's probably a particle that goes back in time and even though gravity is transmitted at the same speed of light we've yet to discover how this exactly translates to other things like the presence of dark matter etc. that would probably require enough energy to pull a wormhole in on itself to prove which isn't really happening anytime soon (hopefully)

Everyone is descended from a small group of ancestors that drifted away genetically and unless multiple groups of humans evolved in parallel from different ancestors then we're all related.

Already addressed in a movie, but he should just not care.

Dreaming is just memory consolidation and planning.

Everything is an illusion of relative perspectives.

People would offer people a ton of money to take the speed route while they themselves take the slow route and the global economic balance would skew even further. Longevity and accumulation of capital is already distorted global economic balances of power among generations, this will worsen it.