I'll give a similar nod on this feature. My workflow in InDesign was to build documents with layers for specific types of content. One global layer for text, another for photos and another for vector art. For example; this would allow me to lock or hide the text layer while I scanned through a long document for an overall view and edit of the other content. I'm fine with the expanded layer view for content, page by page, but this seems better suited to Designer (Illustrator) which would be more prone to many separate vector elements such as a busy graphic.
Being new to Affinity products I'm more than happy to date. I'm being careful not to make a direct comparison to my Adobe background since I'm in a new country now with new ways.
One last point; when Adobe first released InDesign, it did not have a TOC generator. This floored me since Adobe had PageMaker at the time which could generate a TOC. The point is that a feature like global layering can still find its way into the program without giving up on Affinity. I'm happy and hopeful.