Is it possible to non-destructively open the SPIKE Prime smart hub?
No, but the damage can be limited and is not externally visible.
I don't know the technical name, but each of the 4 corners are held in place with these fasteners:

Using a tool of the same diameter (2mm), they can be pressed out by applying force to the end of the fastener at the point shown below:

This does damage the plastic slightly where it contacts the fastener, but if it is only done a few times the fasteners should still hold securely when reassembled.