I guess that's subjective and depends on what kind of work you do. For technical drawing, you are perhaps more interested in sizes that disregard strokes. But for artistic drawings, the "size" of an object is synonymous to its area coverage.
I think some things (e.g. selection outlines) should probably always use the visual bbox. But the line between "technical" and "artistic" can be very fine. Even if we ignore technical users, there are artistic users (including myself) who sometimes require geometric bounds -- tiling is one of the most common cases, but there are others as well.
We need to have a better solution in those situations, because there, the lack of geometric bounds isn't just annoying, it's debilitating. I just wish I knew what that solution was. :/
-mental