I am reminded of the excellent work by @Pseudonium on the Obsidian to Anki script. To summarize a series of posts from that long thread, it developed over time to include different methods of defining what a “block” of text is as far as that script is concerned.
It started out as predefined markers - literally START
and END
- but has progressed to being able to use headings and the text following them as well as custom regex expressions to let you define what constitutes a “block”.
I think I agree with @Dor in the sense it feels like there is room for advancing the definition of a block from the current single method to something more diverse, potentially all the way to allowing custom definitions.