Probably everything aboard the lander was “surveyed” (written off the books as lost) before the launch. In a high-risk mission (such as the Normandy landings), that’s not unusual. Also, the lander itself was not coming back, so perhaps they assumed that any part of it not already on a checklist (like film cartridges) would be left behind as well.
And it may be for the best that the camera didn’t surface until now...people have been incredibly careless with historic items, soon after the fact. The original videotape of the first moon landing was lost, stolen or taped over along the way...what survives now is more akin to a kinescope (recording of a TV screen image) rather than a copy of the original video.
And it may be for the best that the camera didn’t surface until now
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One would think that there would have been a lot of discussion/analysis on the performance, usability, reliability, etc. of the camera if for no other reason than to make improvements and/or leverage lessons learned and insights for future missions. I’ve supported other types of missions before (of the military variety) and there was great emphasis on post-event analysis. One of the main topics was always on what worked, what was “problematic”, and what could have been better. Equipment performance is central to this type of discussion.