one has to differentiate between SAP the product and SAP as implemented by random big-co. The parts that are user actively confusing and user hostile are usually result of customization done during the implementation (and motivated either by requirement to keep some existing ad-hoc process or by requirement to have some report contain something that is otherwise irrelevant for its contents).

It is certainly not true that SAP does not care about UX (in fact the reason why SAPgui has it's decidedly non-native look is result of some UX research in late 90's), only the UX they care about is not about easy onboarding, but about efficiency of use. And by the way in my opinion SAPgui manages exceptionally well to combine power user features with discoverability (on the UI toolkit level).