Cool. I'm a bit unsettled that my camera's green dot didn't turn on for it though.

VisionOS has this too. I mapped it to a triple click of the button for when eye tracking becomes inaccurate.

Cool! That works surprisingly well. But how do you click while using this? Clicking on the trackpad doesn't work, when it's tracking my head.

That's a separate option. The option above head tracking in those settings allows for adding your facial expressions (smiling, blinking etc) as shortcuts for clicks.