Maybe it's more accurate to say that complex social problems can't be solved by technology alone. There's been a rarely questioned assumption that a bunch of hackers in a room together can single-handedly disrupt and reshape society in constructive ways. I think we're seeing now that this is a naive and even dangerous point of view.

To elaborate on your examples, things like sewers and wheelchairs benefit us but they depend on a social and legal framework to do so and require coordination, planning and consensus to be useful.