There's also the chance that those robots find something so compelling it reinvigorates human space flight.

That's not a reason not to. That's a reason to also send out robots.

I can see how cheaper and easier can be viewed as 'not a reason not to' but the crux of the issue is that robots will do a better job than humans anyways.

Why spend more money and effort to do something less effective?

Because it is cool and inspiring. This doesn't have to be about min-maxing.

Budgets are always going to be finite, and eventually you will have to choose. Until we run out of space to explore with robots, we don't really need to send out humans.

There is no "need" with exploring. Just do both. We'll learn more about living on other planets if we actually do it.

My thought exactly, well said.

Why not do both?

Because there is no benefit of sending a human rather than a robot. The article disuses this at length.

This quote is a reasonable summary, I think.

"The crew will not live in a Martian pueblo, but something resembling a level 4 biocontainment facility. And even there, they’ll have to do their lab work remotely, the same way it’s done today, raising the question of what exactly the hundreds of billions of dollars we’re spending to get to Mars are buying us."