Most of the resources in manned space flight are devoted to not killing the astronauts. Just sending robots is way cheaper and you can do a ton more projects for the same amount of money. Landing a robot on a comet is way more interesting than the 130th trip to a space station that’s only 200 miles away from earth (a person can bicycle that far in a day). And going to Mars is impossible for less than hundreds of billions of dollars, if it’s possible at all.

Sending people into space was a stunt, like climbing to the top of Everest. Having done it a few times there’s no point in doing it again. People say, oh you learn so much from it, but that would be true for trying to live on the bottom of the ocean or in treehouses or whatever. Romantic nonsense is fine but manned spacedlight is expensive and requires a ton of talented engineering that could be better used elsewhere.