Not that it couldn’t be trivial in the abstract, but I’m struggling to imagine a use for a nested list item containing a table of blockquotes. It doesn’t seem at all surprising that a tool wouldn’t anticipate that.

Things from the design world, like Acceptance Criteria would happily require it.

Is a lightweight easy-to-read plain text markup language the right tool for that job?

Absolutely! The writers are generally not highly technically experienced, but have to produce highly technical documents that need to be regularly reviewed and changed for years at a time.

If you're going to do this, why not generate Pandoc ASTs directly? You can do so from a number of languages and they support (by definition) a superset of any given markup's features, with blocks to call out directly for things you can only do in Latex.

I assume the original question is asking about programmatic document generation, in which case working with a real AST is probably also a productivity and reliability win as well.