One may hate on Musk for a number of very good reasons, but it cannot be denied him, Shotwell and the rest of the SpaceX team have thoroughly kicked the established space industry mooches into their asses.
Anything he say should be taken with the proverbial grain of salt.
I don't think he is a complete fraud, but I would not bet my shirt on his Mark colonization project.
What is a billionaire gonna do once they get to Mars?
Undergo profound physical atrophy leading to organ dysfunction and eventually cancer ...
... since Mars gravity is something like 1/3 that of Earth.
We barely have the capability of living long term on Antarctica, and it has plentiful water, oxygen, gravity, a magnetic field, and doesn't have lethal radiation. Until I see a 100K population colony on Antarctica, I'll be unconvinced that we even have a prayer of building a 1K population colony on Mars.
I'll admit that I'm not sure what the point of a mars colony is either, except for science and to act as a forward space outpost.. maybe it would be useful for industrial purposes? I guess you wouldn't have to worry about utterly destroying the environment.
If it were mostly self sufficient it could act as a seed to repair earth society in the event of a catastrophic asteroid strike or nuclear war, I guess