'He kept going until he couldn't': why do boomer men refuse to slow down?

What if that is the way he'd rather go out? Doing what he's always done, and enjoyed his entire life. Rather than be in an old folks home drooling and unable to wipe his own ass?

I don't say this to be mean, I say this as a legitimate question. My grandpa chose to go off chemo so he could go out with dignity and as he chose. You hit a certain age and you know that no matter what death is inevitable.