When I try to import a custom SF Symbol exported for XCode 15 and try to import it in Xcode 15 beta (15A5160n), I got the error:
The SVG file provided for the symbol image set 'rings.heart' is not suitable: Template format 5.0 is newer than the version that this software supports (4.0)
Is Xcode 15 Beta not ready yet for Custom SF Symbols 5.0?