There are these tiny little consumer "ball" cameras one can put on top of their head or mount to a stick that can do it for only a few hundred dollars retail.
Here's a very cheap example below $150 retail. Obviously, mounting this kind of thing on top of our heads is probably NOT a desirable option but cameras spread around our heads should do the trick. Whether that adds significant cost and/or storage demands is up in the air, but if a $150 camera can do it, I suspect Apple could find a way to deliver the same capture range... maybe in a V Pro Pro?
And yes, I'm sure that $150 camera does not live up to the quality of the cameras Apple are probably using in Vpro. So I don't mean that for $150 more Apple could have delivered 360 degree video capture. On the other hand, I doubt it would add substantial cost to achieve that kind of capture if Apple had gone after it.
As is, Vpro "spatial" is going to be limited to "out front" capture whether shot with Vpro or iPhone. But as OP offered, it would be nice to capture the view all around, so that one could then playback and look all around and see whatever was out front, full left, full right and even behind. That already exists for many years now with cheap retail cameras. Look up any VR 360 degree videos on youtube, play, click & hold & pull left, right, up, down or look fully behind. Here's just one of
MANY examples...
Play it. Click on it & hold & pull the view around to any direction. Conceptually, with Vpro, there's no pulling around- we just look over there or up there or back there and see like we are "there" now. But the abundance of such videos on youtube shows that the tech to capture it has existed for a long time... and if many "they"s can do it, Apple can too.