Let's clear this up - the last person to be called Gary WAS NOT BORN IN 1992 and they will not die out by 2050.
The story comes from the Daily Mash, a very funny site but really, when this quote was used, everyone should have known it was a joke:
"Logan, who tours maternity hospitals promoting the name Gary, said: 'We’ve already lost Alan, the last Ken is living in a shed in Farnborough and the Lees that were once at every party claiming they knew martial arts are increasingly rare.'"