NASA has plans to send people to Mars simply because otherwise Congress won't continue to approve huge budgets. And why does Congress approve such budgets? Because the proposed mission will have contractors in nearly every State and component manufacturers in a great many Districts. In other words, $100 billion is being flushed down the toilet to buy votes; e.g. situation normal for the USA.

In reality there's zero purpose to any manned missions. We learn infinitely more from robotic missions - witness the last rover-helicopter mission which returned far more data than any humans could ever do. Unfortunately ordinary people can't distinguish between sci-fi nonsense and reality, and ordinary people want to gawp at spectacle and have zero comprehension of real science. So the achievements of (for example) the James Webb telescope pass unnoticed. So instead of spending $100 billion on missions of real value, the USA will squander it on a stunt that is not only totally pointless but also will likely kill or seriously damage all those who are foolish enough to make the trip. Once again, generic human folly wins out over any attempt at reason.