In the DJI Vision app (and GroundStation, I believe) users had the ability to plot their waypoints on a map before beginning a flight. This was a great feature that I used on my Phantom 2 Vision Plus.

Why is this NOT the case for the DJI Go app that runs on my Phantom 4?

I know how the Waypoints feature works in DJI Go - and it works well - but it was pretty convenient to plot the course before flying it. It was also especially useful when planning flights and budgeting power use.

Is there any chance this will be back? I'd rather not switch to a 3rd party flight control app.

I'd say they did it so that people don't plot a flightpath in advance an  mis-calculate obstacles or heights, which will likely result in a crash.

Use Litchi, it's superb.

Litchi is the way to go for waypoints, VR, foucus, Point of interest!

Litchi rules!!!

AutoPilot from AutoFlight Logic.  It double-rules.  For IOS.

It is more safe when  the drone's sets the points by flying it.
On a map you can not see the tree branches on the electrical wires  so flying it manually first makes your route much safer