No one will leave because they're now required to stay to the legal limit to make up for the seniority you'd like to steal from your peers. That's what we somehow can't hammer through your skulls. You are actively seeking to reduce my anticipated compensation from now until 65 to extend it farther. I won't arrive at 65 in the same place if the mandatory retirement age is later.

It's like the Ring of Doom. No one can be trusted to make a rational decision when they're holding it. You have to commit to the outcome before the moment of truth arrives.