That's not at all what happened. NT was a completely new OS foundation, unless you think Dave Cutler borrowed pieces of his own VMS work at Digital.
In some alternate Microsoft strategic universe it might have been released as "OS/2 3.0", but it has effectively no inheritance from the OS/2 1.x/2.x/3.x code base.
In some alternate Microsoft strategic universe it might have been released as "OS/2 3.0", but it has effectively no inheritance from the OS/2 1.x/2.x/3.x code base.