I think the space economy will just be a lot of what you see now. There isn't a bunch of necessary resources for Earth's development worth collecting from the vastness of space. There isn't any reason to populate inhabitable locations vs staying on Earth.

Expanding into the solar system mostly just has research value. The Space Economy is just ways to use the immediate space around Earth to benefit Earth, like satellites.

Things like researching exotic materials in space will become less and less useful as computer modeling improves, you don't need many labs in space and we aren't going to convince people to move off Earth to conditions that are way less healthy other than the few hardcore scientists who can study the preserved records of the solar system, but even there robots will scale upward to do that better because it's so hostile and so vast and humans take so many resources to send into space vs robots.

Humans will develop brain to computer interfaces and that will change how we view space exploration and future development. It's all about super high efficiency and low mass, not mega structures and giant spaceships.

We will have self assembling robots that can build anything, even a new Earth and that will happen long before we can get humans to another solar system while at the same time humans can upload their minds into machines and gain virtual immortality and super high efficiency/low mass existence. All that will happen LONG before you can travel anywhere all that interesting through space, probably in the next 100 years.