Am revisiting the idea this weekend - had dropped it as my RPi4 died and I had moved to another SBC (NanoPC T4) that is hardly drop-in compatible to the Rpi camera lineup.
It’ll use a 10$ Pi Zero to turn the Pi Cam HQ into a USB UVC webcam. From there, it should JustWork (TM). I gain almost 100% sensor size, going from 1/3.2" to 1/2.3", smaller pixel size even with 2x2 binning and faster bandwidth. Down the road, also possibility of bluetooth connection if needed (although then still need to power the Pi Zero which is powered via usb otg anyway) and to add other pi-compatible sensors (thinking GPS/temp/humidity). Funnily, Arducam sells a picam-to-uvc board, for 100$. Here total cost will be 12-13$ (board + small SD card).