Curiosity cost us about $2 billion and it has some of the most state of the art systems on board. Among these was its drill, which was supposed to provide some of the most important science from the mission. And as my use of past tense probably belies, it broke after 15 activations. [1] Redundancies and the best NASA has on it notwithstanding, it remains broken. They've now, a year later, developed a high risk idea to try to get some drilling done. We'll see how that works out. This would have been something a human on site could have repaired in relatively short order.
The point is that robotics and other technologies are advancing extremely rapidly, but they're still not anywhere even remotely close to being able to compare to humans in general purpose functionality - let alone improvisation. Don't forget that those amazing videos of Atlas are the result of countless takes and on-site specialization. This [2] article describes the results of the most recent DARPA Robotics Challenge which featured all the big names, including Atlas. The competition included tasks like walking, opening a door, and climbing up stairs. The most ostensibly difficult would be navigating a specially modified vehicle after having humans carefully place and suspend their robot inside it. And the developers all knew ahead of time exactly what the tasks would be and the circumstance, except for one surprise task which ended up being pulling a lever. The long and short is that it was a disaster. Quoting the article:
"If there's a single lesson from the [DARPA Robotics Challenge], it's that humanoid robots are falling robots. Also, that the road to humanoids that aren't so clumsy will be long, and strewn with shattered components. If DARPA doesn't hold another version of the DRC, then the first one will have been little more than a grim status update, and a self-contained failure, for the few of us that realized it happened."
The point here is that we are a long ways away from robots that can remotely compare to humans for general purpose tasks. The timeline for getting to the Moon and even to Mars on the other hand is very near future.
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Beyond all this, space exploration is not just about science. Did you know China put a probe on the moon in 2013? Technically it was a rover, but back to those robotics problems - it became a probe. It was the first time anything had soft landed on the moon since 1976. If you did know this you're probably already a huge enthusiast in the field because the world collectively yawned, even though it made some groundbreaking discoveries including discovering the moon's geographic makeup was far different than we thought. That discovery is playing no minor role in driving the recent moon race.
But people want to see and discover space themselves. And there are lots of people willing to pay lots of money for the privilege. Two individuals have already purchased a Moon flyby from SpaceX - scheduled for next year. And even though a flyby is nothing compared to a soft landing, that will not be met with a yawn. Action requires money. Money requires public drive. Public drive requires manned operations.
[1] - http://www.planetary.org/blogs/emily-lakdawalla/2017/0906-cu...
[2] - https://www.popsci.com/darpa-robotics-challenge-was-bust-why...