Block referencing allows me to include the information in a paragraph in a separate document without copy/paste. Then if I edit the block it is edited everywhere. It is hugely powerful. I’m loving Obsidian but have not yet cut the cord to Roam specifically on this one issue. Where I see Obsidian “not yet there” is on workflows that allow me to compose in one note while rapidly scanning for and incorporating content in other notes. I may not have figured it out yet but currently I’m finding it quite kludgy to edit in one window and then review other windows for content to include.
An example workflow in Roam that has been linked in these forums before:
Nate Eliason using Roam to quickly outline article
Personally including blocks from other pages as a linked quote is a huge part of creating summary pages etc on a given topic.