I couldn't immediately figure out here whether we're talking
0. Microsoft's supported products default enable this worthless "authentication" feature
1. Microsoft's supported products provide such a feature behind a UI that's not clearly marked "Danger: Do not stare into laser with remaining eye"
2: Microsoft does still support this, behind some Registry nonsense most users do not understand and once enabled it doesn't turn on the "I am a toxic waste dump, leave by nearest exit" warning signs on affected machines
3: Microsoft doesn't support this at all but some 3rd party commercial stuff does and customers really do love their crusty archaic 3rd party garbage
4: But this long abandoned SCO machine we've kept on life support for twenty years!
5: What does "supported" mean? Windows NT is scary, we're still on Windows 98 here.