If you haven't noticed, the space stations we do build require international cooperation and are basically just a bunch of rocket sections stuck together. The ISS, in all of its glory, took years to assemble and has some serious design constraints.
A project of that magnitude would require lots of highly specialized parts to be launched into orbit first, or, we somehow manage to build an entire fabrication facility in orbit where it can process raw materials.
The concept of a rotating ring is simple. Developing the means to build it is hyper-complex.
You don't have to build a whole ring. You just need a boom and a counterweight.
I guess the hard part would be that a truncated-circle-sector-shaped room is more awkward to launch than a rocket-section-shaped one of equivalent usable space. (Also, you need a tube and a ladder down to a docking port at the center of mass, because spaceships can't line up with a target swinging through an arc.)
Not THAT complex. They already have several prototypes they're planning on testing. They won't be giant rotating stations, but rooms of a few meters across. It doesn't take much rotation to get useful amounts of g's.
basically just a bunch of rocket sections stuck together. The ISS, in all of its glory, took years to assemble and has some serious design constraints.
I mean it sounds simple, obviously doing that we be a ton of work, but it seems very feasible. And doing that would be an incredible starting point for space industry. From there, we could send out automated probes to capture trojan asteroids from earths orbit and launch them into lunar orbit for collection. We could even put them in a non stable orbit that bleeds off orbital speed and eventually they bleed off enough to land while staying in almost one piece depending on the type of asteroid.