It was absolutely sold as a replacement. And it's gone now because literally nobody wanted it, used it, or understood why it existed. Sure, you could still find the old Paint in a disused lavatory behind a locked door with a sign "beware of the leopard". It wasn't even installed by default, unlike the 3D version, or do I recall incorrectly? Even MS isn't so stupid as to ship two separate accessories both called "Paint" in the same OS by default!