As I said, it’s more complex than that. Your idea works well only if the pad is connected to nothing else, including tracks, zones and other pads. But in real world a net consists of different kinds of items which all should be connected to each other directly or indirectly. The only logic which works everywhere is to handle a net as areas which are disconnected with each other, and each area includes one or more items, and the items can be anything which can belong to a net: a pad, a zone, a track/via.
Imagine a net which is split into 100 separate areas. Each area can have e.g. 100 pads, 100 tracks and 100 zones. (Not really, but exaggerating works to find out logic.) (EDIT: and, as Jon pointed out, zones can be split into separate areas, so that one zone can be part of each split area.) Or there can be 3 areas, each having 1 pad only. How would you report this so that the report template covers all possible combinations? And how would you, as a human being, decide which are the relevant parts of those split areas, so that you could write the report to other human beings so that they immediately know where to look at and what is really not connected, and where it should be connected? If you can come up with some logic which works for all cases, please tell. I believe it will be similar to mine.
If a net is split into separate parts, each item in each part is logically disconnected to something else, even if the part forms the majority of the net.