Ahh, I didn't realize it's as simple as a popup GUI asking for authentication — my bad, thanks for clearing this up for me, works perfectly.
I gave OverSight a try as well, but it looks like it only monitors the internal mic and FaceTime camera, and I actually use my MacBook Pro in clamshell mode with an external audio interface (and no webcam). So even when I disconnect the computer and use it as a normal laptop at the end of the day, as right now, I still see the orange dot even with all apps fully quit, and OverSight is completely blank.
Anyway, thanks again! I'll submit a bug report with Apple. I found other reports of this and do believe it's a bug.