This feature would be helpful when you want easily linkable blocks/headings as well as consistency in the process regardless of where the blocks/headings are moved.
Firstly, I understand that moving or extracting a block/heading into another note will break links to the block/heading. A solution to that is outside the scope of this request.
What I am thinking of is a middle ground between atomic notes and blocks/headings via block/heading aliases. If blocks/headings allowed you to define aliases, you would be able to more easily find that block/heading by its alias when trying to link or embed, regardless of a changing block id or heading name. So in a way it would assist with any difficulty remembering the names of headings that have been changed.
Of course, in the case of blocks, you could define a custom block id, but this workflow can feel brittle and exacting, and dependent upon no use of spaces. Plus you need to remember which note it is in. I see avoiding this limitation as one of the major improvements gained with this request. After extracting a block/heading, the process of linking to or embedding that block/heading would be the same as before via the alias, thus making the block/heading feel more atomic. However it is important to remember that after extraction you would still have to fix the broken links (see links below).
Some relevant requests: Note Composer: links to blocks and headers should be updated when extracting, Automatic/inline update of links to headers and blocks when they are modified (no extra dialog window)