I do not think this is a bug.
It worked like this since AC16 when the Morph Tool was introduced.
When you are using CTRL-SHIFT to select sub-elements you WANT to find Edges and Faces of Morphs, so of course the Magnet is active regardless of whether it is turned ON or OFF in the Arrow Tool Info Box.
Of course, when you stop using CTRL-SHIFT, the behaviour or the Magnet return to the way you would expect it.
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