That's pretty silly. No ones driven around the world 100 times. But we know full well we could. The technology we have. from several different projects. It just has to be put together. It may even fail the first couple of times. But we can do it. There's nothing to be proved. all the separate components have been invented and proved.
I don't think it is silly. You don't seem to grasp that it's a completely different pursuit entirely sending humans out to Mars. How long did it take NASA to design a spacecraft capable of landing on the Moon? How many different iterations of launch vehicles etc. did they go through? They may well think they have the technology, but until they do it and prove the technology then no-one knows it'll work.
Sending probes to Mars is one thing, it's easier because there are less considerations. As soon as you introduce Humans into the mix you have a whole host of additional issues:
1. Physical effects of exposure to high-energy cosmic rays and other ionizing radiation.
2. Physical effects of a prolonged low-mavity environment.
3. Physical effects of a prolonged low-light environment
4. Psychological effects of isolation from Earth
5. Psychological effects of lack of community due to lack of real-time connections with Earth
6. Social effects of several humans living under crowded conditions for over one Earth year
7. Inaccessibility of terrestrial medical facilities
Source
Then the spacecraft has to be larger, with more powerful propulsion systems. A Lander Module would be needed, powerful enough to escape Mars' mavity etc. etc. etc.
I don't think they can do it. Not any time soon any way.