i.e. even a disused airport does not count
But.... The landing or departure of aircraft HAS been resumed - because you have landed there, despite it generally being marked as "disused".
not designed for;
not equipped for;
not set apart for;
not affording facilities for;
One could argue - even in your rather extreme case, that if nothing else, the aircraft (irrespective of type) has been able to land, therefore, in context, as you suggest, the landing site chosen "afforded" the aircraft thus being a suitable location for such purpose.
ps: sorry for splitting hairs - this doesn't amend the fact that MSA in the "class G, IR(R) world" generally means Minimum Safety Altitude, which relates to being at least 1000' above the highest obstacle within 5nm of track.