Why can't Cubase and Wavelab share things?

It seems like both are Steinberg products but what seems to be “normal” for Cubase users is completely unavailable to Wavelab users. Is it the programing that will not allow Cubase features to be ported over to Wavelab or is there some 'internal turfdom" that will not allow Cubase and Wavelab developers to work together collectively? This “split” seems to have been around for a long time. Just wondering…