As eriond suggested, the T&Cs as written seem to be new, pretty sure some of them weren’t there the last I checked (though that was at least an year ago). For example, they now also include that ridiculous ‘no overnight’ nonsense — which also covers transit J passengers who have been sold overnight connections by MH.
https://www.flyertalk.com/forum/37493124-post77.html

Definitely a step backwards if MH starts enforcing this for passengers… maybe they’ll claim it’s only for customers purchasing access, but I can foresee a future where — especially without this clarity written into the rule — an overzealous lounge manager decides to start forcing it onto J / elite passengers as well.

As I said before, MH introducing such rules *is* just going to annoy their customers who spend significant money…