I’m surprised that nobody has expressed interest or similar requests for page content filtering.
Page filtering has the potential to make Obsidian the markdown version of Jupyter Notebook. We can develop and ellaborately document code in one wiki style page. Once Obsidian filtering is in place and has an API to match, a plugin can take care of syncing only the code styled content in the page to your preferred compiler.
This possibility is wildly exciting to me. I hope others see similar potential and enough interest is drummed up to convince the developers to make it happen.