Yeah, I know that. But many of the rock gods would just turn down the volume on the guitar for more overtones in the clean tones. That doesn't seem to work so well with the Kemper. The low gain profiles just sound better.
I suppose a lot depends on the guitar. Most of mine have a treble bleed capacitor on the volume knob so they clean up great with the Kemper. I typically run 3 - 4 gain range and roll it back to clean up.
One thing you can do is use a mid to higher gain rig and morph the gain down for the same effect as turning down the guitar volume. I made about 10 test profiles of my THD BiValve non master volume amp with the volume ar every hour on the clock face and compared the original rig to a higher gain rig with the gain reduced to match the original rig and they didn’t sound the same. However, reducing the gain did actually sound pretty much identical to turning down the guitar volume. The test profiles are in RigExchange of you want to test it yourself.
make a performance
In slot 1 use a rig with gain at say 3.
In slot 2 use a rig with gain around 5.
In slot 3 use the same rig as slot 2 but reduce the gain to the same number as slot 1 shows.
In slot 4 use the same rig as slot 1 but increase the gain to match the rig in slot 2.
Now compare the pairs and compare higher gain with guitar volume reduced.
I think they were direct profiles if I remember correctly so you will need to load a cabinet as well or use them with imprints.