In terms of what we decide to build, impossible vs. impractical is not a particularly interesting distinction (that distinction can give rise to fun science fiction). Practicality is at the core of good engineering, and possibility is just the first of many steps in evaluating practicality.

If we're going with a distributed approach, there are other ideas that are more practical. For example, send 1 KW boxes to a million people (< 1% of American homes, but there's no reason to limit this to the US). Very roughly, these are beefed-up gaming consoles - you could even start with existing gaming consoles. That box plugs into electricity and ethernet. Pay each of those people $1,000 a month to leave their box running 24/7. For people with a lot of solar at home, it could be a nice income stream. At $1B per year for payouts, it's far cheaper than doing it in orbit. And it doesn't rely on promised but as-yet undelivered technologies. But data centers are probably more practical.