...As far as astrology goes, I'll leave that to others, but I guess you might want to seriously consider this: unless you've heard the tube-like or tube-type magic or essence with your own ears, you might not know what you're missing. I percieve the description of soundstage expansion as that sort of third dimension that is evident when some degree of "air" around the music is presented; a common trait with fine tube/tube-like systems. In other words, SS is known for sounding anywhere from the cold, analytical extreme or maybe even two-dimensional to warm or sweet. The best of tube/tube-like sound generally adds depth and an added dimension of sorts, possibly even more of a realism that can be surprising; at least that is mostly what I percieve as the difference...You will however, hopefully know it when you hear it.
I'd probably humbly encourage electroking to get out to an audio show or event, show or at least maybe some kind of local event or meet and see what there might be to experience, either totally tube wise, or at least tube-like wise. I'm kind of convinced in advance that you'll "get it" when you hear most any Pass amp with high-quality peripheral equipment, or if not, you might try checking in with some type of tube preamp and/or tube amp combo system.
Your mileage may vary, although you could work at this either "backward" or "forward", meaning that you might want to hear an all-tube system, hybrid combo, or possibly a class A Pass SS system in that, or reverse order, to achieve your personal reference for various grades of anytyhing from truly tube to tube-like SS sound.
Speaking of actual tubes in their native audio environment, one of several tube types that easily comes to mind is the 845; when it's delivering its magic from within a well designed and built amp, it's difficult to imagine much of anything else that can deliver all the true-tube goods any better.