It's just a matter of time before one of the big ALPA carriers goes bust in a big way and puts 8000 pilots on the street instantly. Many of these folks will suffer from broken pension plans, they will not be financially ready at age 60 to retire; especially not because in the USA social security pension payments don't kick in until age 62 at the earliest.
Most ICAO countries have already adopted the age 65 rule as a matter of practical reality.
As to age 60 policy: ALPA is a self centered, narrow minded flying club that remains out of step with a fast changing world.