Agreed and I've just started thinking about replacing the HU on my 2021 premium. There are a number of vehicle settings only accessible through the HU, lights, defogger, doorlocks... are these all lost with an aftermarket HU? I believe the Maestro modules only allow the retention of steering wheel audio controls.
-Dave
In my 2020 Premium, I believe the settings you mention can be adjusted using controls on the steering wheel, along with the display between the tachometer and speedometer.
The one thing I haven't been able to adjust, after installing a Kenwood head unit, is the clock on the center-dash display - so I just cover it with some painter's tape during the part of the year when it's 1 hour off from the clock on the radio (which does update for changing DST - probably due to the Bluetooth connection to my phone).
With the iDataLink Maestro firmware now updated to support Foresters newer than 2018, I'm going to have mine installed - to enable the OBD and steering wheel interfaces.
I have no idea whether the OBD serial bus interface connects to the center dash module which contains the clock.