There is a sixty-year tradition now of pieces for instrumentalists + tape or live electronics, where it is the synthesized material that is spatialized through loudspeakers around the audience.
Completely different context than using a synth in a digital realm. I'm not saying you can't spatialize synths, but that the waveforms are unlike sounds we encounter in the natural world so it takes adding a bit of "naturalness" to them to help our ears understand where they are in the space around us. That's something that's harder to do in a digital environment like a spatial audio engine, but is easy enough to work around. Just an ancedote on spatialized audio in software, which again is different than what you're talking about.