Jeff Bezos, like Elon Musk, sees the future of humanity in space. But instead of meaningless (according to Bezos) colonization of Mars, Jeff proposes to explore space using O'Neill cylinders. How to do it and what are the advantages?
I think that both options are meaningless at the current level of technology development.
We still don't have a debris cleanup program. But there are a bunch of ideas on how to send even more garbage there.
The advantages of an O'neill cylinder or other space colonies is you can put them wherever you want. Namely closer to Earth and Cislunar space so they're not cut off by significant light lag for communications, and get the fuller benefit of solar power by being closer to the sun than Mars is. Plus once it's going, you can move it anywhere under low thrust, kind of like mobile city. So if there's a good asteroid going by, you could in theory follow it and go mine it.
Other advantages, you can build them to spin and produce 1 earth G, so no issues with bone density or any other gravity related illnesses or developmental problems in children (assuming bio-tech doesn't come up with alternative answers) And you can cover them in asteroid debris to block any/all solar or cosmic radiation. And with a mass of a small asteroid, you've got almost no lift costs to send people or materials away from there to other destinations in the Solar System. Leaving a space colony would be cheaper than even lifting off from the Moon.
And further down the road, if we never develop tech to move really fast in space, just sending an entire space colony can make long distance trips to the outer solar system, or maybe even someday interstellar, do-able since people would be more willing to go if their entire community and all the comforts of home goes with them.
What is unsaid though is how you actually BUILD such a ginormous tube in space from (presumably) asteroid or Lunar materials. OTOH, we have a pretty good idea of how to dig on Mars or Luna, or use existing caves or lava tubes to hide from radiation. And in theory, the low gravity of Mars or the Moon isn't a show stopper long-term. You could build a city/base as a shallow cone to spin it and create a centrifugal force vector combined with Mars or Lunar gravity to create 1 G like on Earth. And while solar power in Mars orbit or further is not ideal, it still works. Just at less efficiency.
Of course, the correct answer is to try both planetary settlement and space colonies, and see which works best. Since we've really done neither before and it's difficult to extrapolate or simulate all the complex factors in both undertakings.