I noticed that in Archicad 27 (and 28 beta too) Label won't calculate global Fill Surfaces, while it calculates global Perimeter and Holes Perimeter and Surface. So I think it's definitively a bug.
Operating system used: Mac Intel-based 13 Ventura
since ArchiCAD 4 now 27 on
MacPro 7,1 12x3,6GHz 64GB ram, powered by macOS 13.6.7
MBP 16" 2019 i9 8x2,33GHz 16GB ram, powered by macOS 13.6.7