It is fun to wax poeticially about they should continue XYZ car, but quie frankly it is based not just on marketing and business decisions but engineering as well.
Case in point, in discussions with my "auto gnome" the Crown Vic was old, too expensive to get up to greater crash ratings, not to mention fuel economy issues with a full frame vs uni-body.
The Crown Vic is Dead, maybe it was time for it to RIP, ditto that the Ranger.
In an off handed hot rod question to my gnome, gee it would be fun to do a junk yard swap of an EcoBoost Engine to an old Sport-Trac. The response? The Chassis wasn't ment for it, too much torque. Again, technology is way beyond what might be now considered a legacy design. Nothing wrong with old school, but not in this competitive environment, for the manufacturer.