I have appreciated a quite nice separation of instruments in my system’s soundstage. I have read many times about people experiencing depth in their music and have never appreciated this.
Category 1: Least expensive
If you are happy/satisfied with a flat 2D sound that becomes a face smacking wall of sound when you crank up the volume, that’s all there is to it. That’s the old school "hifi" that many dudes have been happy with for decades. Don’t worry about depth or 3D if you fall in that category.
Category 2: Very expensive
No matter the recording, some level of partial 3D and pertinent depthwise spatial nuance is created primarily in the digital domain with FPGA dacs, processors like BACCH, etc (still inside the domain of channel based stereo)... There are also elements of speaker design, analog circuits design and setup - speaker positioning/listener positioning/room, etc that play into its conduciveness.
Category 3: Can be as expensive, more expensive or less expensive than category 2
True immersive 3D envelopment/immersion/detail/full on spatial nuances/etc, which is more representative of live unplugged events in great acoustic spaces can be accomplished with object based audio, i.e. more than 2 speakers and pertinent object based audio processors.
Note: "All knowing seers" in the 3 above mentioned categories will claim that they achieved audio nirvana in said category (to each his own/who cares).