Earlier quoted context omitted.
The research that was put into finding optimal processes for those non-differentiating business functions can of course be invalidated at a later time. We all put lead in gasoline because it seemed optimal, then later we kept putting it in gasoline well past the point it was known to be harmful, because everything was designed around it.
Sure. We also found out that Micro-USB as a charging plug for phones does not cover all new uses. But standardizing on Micro-USB was still the correct course of action at the time.
What OP is saying - Perhaps SAP 'optimal processes' made absolutely sense few decades back, but when new time came and world or best practices changed, those optimal processes were no longer optimal, but still one needs to keep using those.. because SAP.
From Micro-USB analogy - world has changed, but you still need to keep using Micro-USB for your USB-C phone... because SAP.