I think the real challenge, at least in the western world, will be getting people to work when retirement at a "normal" age is not on the table. A lot of people work boring jobs with the knowledge that they're done at 60 or 65 and if health permits can have 10-20 years of nice retirement. It's going to be a tough sell for a lot of jobs to convince people to want to just do them until they die. For interesting jobs, I think many do this anyway, but if you're some pointless cog in a bureaucracy, you're probably just counting down days to get your pension. Losing that would make people rethink the whole thing (and hopefully enjoy themselves more)