Not sure how much you have used IQ but RLV is by no means sufficient to run all of BW's operational needs.
No doubt that significant investment would have made it work but they invested in HANA instead. IQ was designed to be an EDW and retrofitting operational features would have been a huge effort.
We have BW to thank for HANA becoming mission critical for Suite use cases. IQ could never have been the database that saved SAP.
And IQ is a great EDW or NLS system to assist with TCO. Think it has turned out quite well?
