It looks like multi-sourced universes will no longer be supported in Business Objects going forward as part of their strategy for 2025 and beyond.
This makes the Information Designer Tool even more worthless than it is now. The tool was already over complicated compared to the Universe Designer and introduced too many points of failure for creating universes. The Mult datasource feature was one of the reasons to use IDT. I think SAP should bring back support for the Universe Designer and remove this monstrosity that is the Information Designer. It makes universe creation much more clunky and overly complicated and requires much more time to create universes compared to Universe Designer.