When the Verizon tech support says that they have been doing their job for 20 years it means they weren't good enough for a promotion ... for two decades.

Sure, or it means they don't want to lick a corporate boot to get a promotion.

20 years at verizon or 20 years in IT?

Or they don't want to manage people. Because that's a completely different job than actually doing the work, yet that's what promotions require after a certain point.