Your example was a generic from science fiction vague statement about a shielded rotating space station.
You have no experience or expertise to back up your statement.
It ignores the extra damage a large space station takes from micro asteroids by being a larger target. It ignores fuel costs of moving something that large into orbit. It ignores food and oxygen limitations on populace. It ignores low gravity birth issues. Radiation issues. Issues of diseases, resources collection and management.
You made a vague uneducated guess of an idea and demanded it be the requirement of others to prove you wrong.
You took the same argument style of a maga conspiracy conservative.
I said we had the technology, you condescending dumbass. All those issues are solvable, they're just not practical to solve. Not right now anyway. If earth became uninhabitable, we would find the money and motivation.
Name a scientific hurdle. Not a logistical one, not an economic one, an actual issue that we do not have the technology to mitigate.
Also, stop being a condescending dumbass. Either thing alone is bad enough, but being both stupid and arrogant is particularly annoying.