I've never understood the point of these cameras - as
Bangkokeasy points out, they're useless in the cruise (even in daylight the resolution isn't really good enough to be able to see anything of interest) and most airlines turn them off for takeoff and landing. In the narrow bodies (eg Finnair 320) with drop down LCD screens, they're stowed away for takeoff and landing (I assume this is mandatory), so your only hope is on a flight with fixed (seatback) IFE with a carrier that's generous enough to leave it on.
As we're no longer allowed flightdeck visits (not in flight, anyway), wouldn't it be better to fix the camera in the cockpit? It could be combined with United-style channel 9 ATC comms
[Dons tin hat and retreats to bunker ...]