Some of the best have taken early retirement and told their organizations to get along the best they can without them.
Others have withdrawn completely and moved into the underground economy. I know a former co-worker who is making moonshine, good quality stuff which earns hard currency. Law enforcement leaves him alone because there are so many more dangerous criminals dealing drugs.
Still others (like me) can't afford to do that just yet and are hanging on not only to earn every dollar we can but because we know it would take at least two, maybe three millennial brats to replace us and we don't want to give them the opportunity just yet.
I see many older guys who originally intended to work into their late 60s opting instead for retirement ASAP; they are tired of PC nonsense and untrustworthy employers, and are packing it in.
The ones to worry about are L-1's from Israel and H-1B's from the IT/IS feedlots of Bangalore.
Or more to the point, the highly-comped B-school a-holes on executive boards who keep pushing offshoring, green-carding, and other bonusable wage-breaking schemes.