Well there are two issues here:
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Its primary intent, as documented, is meant as a convenient tool for running quick proofing copies. So in a sense we aren’t putting a lot of thought into it, as it’s mainly meant to be used with A4/Letter layouts you’d print out yourself. It is certainly not meant to replace a serious tool for this, and the method it uses is not very clean, requiring the document to be littered with bookmarks.
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What you are seeing on Windows is however flawed in that the feature was never completed. What is supposed to happen, when you paste a ToC clipboard, is the following:
Thus, even with point (1), one could still cobble together some fit for purpose front matter entries, presumably where each set of front matter is sized to match the compile settings they are meant to be used with. Without that, point (1) is made a much stricter statement, particularly if you have a lot of indents you don’t want to lose.
All of this aside, unless you are indeed looking for quick proofing output, I would myself find no reason to ever use the tool for anything serious (and to be honest, probably never for proofing either). If I were to use traditional rich text at all, then the only method I would ever use is described in this how-to on properly formatting headings. The side effect of doing so means a good document outline in the compiled file, which any good word processor can take and turn into a “real” dynamic table of contents. This takes a few seconds after compiling.
The linked post also contains a sample Format, which is an alteration of the Paperback 6x9 format, to use styled headings instead of the essentially meaningless raw formatting the default format uses. But it describes how that format was thought out and modified, so that you can do likewise with your own setup.