Windows XP already has support via a hotfix. Windows XP dies in 144 days, anyway, so anyone left using it by the time this takes effect will be using a hopelessly insecure system for some time already.
it won't die. it will be used for years by millions of users. that some company stops issuing security updates for a software means nothing to most users. it probably will even make them more happy because they are not nagged by update messages all the time.
People can still use it. But it's dead, insecure, and unsupported. Just like Windows 3.x, 95, NT, 98, 98se, 2000, etc. People still use all of those, too.