this is very true - my fathers previous vehicle as 1996 Grand Cherokee Laredo - it has permanent AWD - in case, you will come to a slide, all you have to do was to push the gas - a bit acceleration will help you out.
on current 1999 Grand Cherokee Limited (the newer model - Series II) it is not that easy - it seems like the RWD comes on only under certain circumstances.. So it handles most time like FWD and RWD comes on anytime, anywhere - more unstable to drive...

And that is the "progress"...