for the longest time, no one in linux land cared about API stability or backward compatibility - then app/game developers realised if they could port a portion of Win32 to Linux via WINE, they could just target the win32 API or at least a portion of it and so long as WINE was installed, their app/game would always work. i find it a bit ironic; desktop Linux is being enabled by re-implementing APIs from another OS.
The Year of Linux on the Desktop was near, and wine would surely be a temporary stop-gap.