Al Gore sort of did disappear after Bush was inaugurated -- and for some time.
People give him a hard time because he went on fighting after the November election when the outcome was still unclear, but I don't remember him hanging around after the Supreme Court decision.
True, Gore did do his climate change thing later, but he wasn't rehashing the election results every week like Hillary Clinton.
I also don't recall Bush Sr. or Dukakis lingering and malingering on the public stage after their defeats.
Kerry and McCain remained senators, so they didn't go into hiding, but they didn't endlessly discuss their defeats.
al gore was too busy saving us and making money