There's also the issue that the cheaper something gets, the more potential it has for uses that simply didn't exist before. Take airflight. Imagine planes/flights were about 2 orders of magnitude more expensive than they are today. So many things we take for granted in society would simply no longer exist. Air shipping - gone, trans-Atlantic vacations - gone (or spend a month both ways on a ship), even military air forces would probably no longer exist - kind of weird when a new jet starts costing in the ballpark of an aircraft carrier.

Try to imagine society without affordable airflight. It'd be so different that it's literally difficult to even begin to imagine all of the implications. And the same thing will be true of affordable spaceflight, but to a far greater scale. One of the most simplistic and "boring" examples of this would be material scarcity - gone. There are asteroids idling around, in reachable distance, with metals and other elements amounting to trillions of dollars on value. Of course the first mega-load coming back will completely crash the market, but that's entirely the point. What we view as scarce no longer will be, thanks simply to lowering the cost of spaceflight. Get it low enough and you could even conceivably create a world where various highly polluting industries could simply be off-planeted, with the resultant products being shipped back.

And I'm actively avoiding anything remotely sci-fi. These are the boring, almost certain things, and they alone already are making the future look utterly alien, based on nothing but cheaper spaceflight.