Is there a different optional approach lights other than the side mirrors? This is the option I bought with my 2019 Ascent Touring:
Enhance your Auto-Dimming Mirror experience by adding the Auto-Dimming Exterior Mirrors with Approach Light.* Open or unlock the doors with the keyless entry system and LED lights located behind the Subaru logo in each exterior mirror help to light the way. Light is cast down from all four doors...
parts.subaru.com
It lights up when I hit unlock on the key fob. Might be a setting to do that, especially since the OP says his doesn't (and Gary, do you mean a button press or also key fob simply in range can trigger it? I'll definitely look for that in settings!). What lights up on mine is the white LED embedded in the side mirror (there is nothing under the mirror - would have terrific utility but I think Subaru simplified the option by having a different mirror glass etc. but common housing). It shines brightly on the front door handle but also lights up a spot on the ground that centers kind of at the front of the rear doors. Looks just like the pic in the link.
Then as Gary mentioned, there are lights on the bottom edge of the doors that are exposed when you open a door (just fronts? I don't recall) and light up the ground.
F.S.