Enter Antarctica. We can send any number of robots to Antarctica, but we're incapable of forming permanent settlements there, let alone off-world.

Consider the food problem: there are plants growing inside at least one of the Chinese research stations. But that's enough for just the few dozen researchers stationed there, who are probably all involuntary vegans.

How are entire cities going to be fed? Constant food supplies would most likely be sent to Ushuaia and from there to the Antarctic Peninsula. That is the fastest route to get them to Antarctica, but we'd still need a way to get them over to West and East Antarctica, which are more distant from any other continent than the Antarctic Peninsula. There are all kinds of other problems, such as the fact that you'd be moving supplies over several different countries' territory. For example, Argentina and Chile dominate the Antarctic Peninsula. What would happen if they hypothetically decided not to co-operate? It's a logistical nightmare.

You also have all kinds of socially constructed roadblocks to Antarctic colonization. The widespread idea that Antarctica is purely for scientific research. For instance, military presences are essentially banned in Antarctica. So are hotels and other tourist attractions. There is a limit to how many tourists are allowed on shore at any one time. (For the record, I do not even disagree with those last two points: overtourism is a clear problem, including in Antarctica.) And so on.

Re-enter outer space. Let's revisit the first sentence of my last paragraph, but take it one step further. Musk laughably wants humans to colonize Mars when they can't even colonize Antarctica, let alone the moon. This is a man of wrong priorities.

Finally, sending a robot to Mars is nothing to compared to colonizing the moon. No problem concerning food, water, shelter, gravity, governance, and many other things emerges in the former scenario, whereas it is abundantly clear that these things present insurmountable problems for contemporary humans in the latter scenario. You probably thought that your comment was some kind of gotcha, ya' nonce.