All this "make people work until they're 70" stuff is just weird to me. I think Ezekiel's "make higher income people retire later!!!" program is designed in part to address concerns that jobs that require any degree of manual labor get a bit harder once you get older. But some of those jobs are actually pretty lucrative, they are just impossible to do once the knees start to go. So you have a good run until you're 60 and then you're out of luck. But, well, hey, only 10 more years until the bennies kick in...
Even leaving the manual labor issue out of it, in my experience, lots of people, even ones with cushy desk jobs requiring little more than cranking out screeds about Burkean humility or bipartisanship twice a week, start to fade after a certain age. I don't mean they all become physical wrecks or exhibit severe dementia, but add together a bit of hearing loss, eyesight loss, joint problems, diminishing stamina, etc... and lots of people just aren't quite up to putting in a full day of work. Not without a good nap, anyway.
More than that, your odds of having a nontrivial - even if cured - extended illness which pulls you out of the workforce are reasonably high by that age. Jobs prospects for such people aren't exactly great even in a good economy.
67 - the age of retirement which is being phased in and will be operative once I get there - is already really old.* You have to be insane or a sociopath to want to raise it even higher.
*Adding, I mean here really old to be expected to work a full work week, though obviously plenty of individuals are perfectly capable.
