I have a fix that may work.
Turn the sound volume up all the way in windows taskbar. This will increase the sidetone volume as well. I don’t know why.
To prevent audio from being too loud you can individually turn the volume down on every program that you use in the windows volume mixer, or in the game bar overlay (win+G).
If you don’t want to do this, you can use a third party tool called Equalizer APO to globally apply a negative gain to the headset so that all sound from the computer will be quieter. Sidetone will not be affected, so it will still be full volume. I don’t know why.
Equalizer APO can also boost the microphone, if your friends say you are too quiet. I’ve done so.
This program works using Windows built in APO support so once you close the program the modifications will persist forever, no need for an extra program running in the background. I use this to apply mic boost without having iCue running.
Here is my Equalizer APO config. Note this is for the original HS80, not the Max, so the gain amounts might need to be changed.