Thank you Mike.

Thank you Doug.

Thank you Mike.

An old shieling.
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Loch Clair in Torridon, Scotland.
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Thank you.

Thanks.

Thank you MV.

Thank you Dave.

A common practice is to use the main subject in a shot to acquire focus lock. That way the distance to the focus point is also the distance to the subject. To acquire that data, all the camera needs to do is identify the focus point (the point used to achieve focus lock). All cameras will be able to do that and I suspect that most cameras could, if required, calculate the distance to the focus point, or provide a reasonable approximation. To be able to identify a specific subject within a frame would require some sort of AI - which most cameras don't have... yet.

100% natural channel for a stream in Torridon, Scotland.
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As you noted in your quote, I used the expression "focus point" and not "focal point". I was referring to the point which the camera uses to achieve focus lock, which in turn refers to a surface, a detail or an edge within the viewed scene which the camera's AF system uses to achieve focus lock. In that way the focus point becomes the point of maximum sharpness.

I believe that is the commonly accepted meaning of "focus point" when referring to photos. Some proprietary software records the focus point that the camera used to achieve focus lock.

"Focal point" is the point of convergence (point F) as indicated in your first diagram.

A wider aperture allows a faster shutter speed, just as a more sensitive film (higher ASA) allowed faster shutter speeds - which is why it was called fast film.

If

Subject = focus point

Then

Distance to focus point = distance to subject.

You may well be right about Lr but what comes to mind is that it's very likely to be the sort of data that the proprietary software provides. In your case that would be Olympus Workspace. Perhaps that's what you're remembering.