Brightness on light group switches lights without brightness capability on

Hey there,

I have a light which only supports on/off.
When I add this light to my Google Assistant and say “change brightness to 30%”, HA applies the brightness to all entities even if they are not supporting it.

I think, this is done by using light.turn_on and the brightness parameter. Sadly, all devices which do not have the brightness capability, are being switched on (in case they’re off).

So I’d like to request this as a feature so that lights without the brightness capability are not modified at all (either staying on if on or staying off when off).

I am willing to contribute in case someone points me in the right direction.