@musicfan2349 I totally agree that the recording and mastering process is an ultimate source of where soundstaging happens, but I don’t think the OP was intending that to qualify as a “component” in the original inquiry (I am assuming this and can be wrong). Yes, it can be a variable such that you can seek a better mastering of a particular source, but often, we as listeners don’t have control over how that is delivered to us until we put it in our room.
FWIW, I’ve heard incredible mono recordings that have incredible depth. Yes, the width is homogenous left to right, but layering is a special characteristic of mono. The Analog Productions remaster of Louis and Ella is an exceptional example of that.