On my system, in Ableton Live 11 or 10 - Scaler on a track and mouse clicking on a pad my VU is -10 at best depending on the Scaler sound. If I add Utility and boost the output of Scaler by 12db I still don’t go into the red like your video. I go to 0db. If I boost the output to the Max of 35db the sound flattens at the top of the VU but does not give me that red that you get.
Mac OS 10.13.6 / Ableton Live 10 and 11 / Focusrite 18/8 / Scaler 2.5
Is that Scaler on your track without anything on the output?