I just wanted to chime in and mention that the folks who wrote organice[0] also came up with an EBNF grammar[1] for org-mode. Also of tangential interest is that work is actively being done on creating a tree-sitter version[2] of the grammar, although that work is not public (yet).

[0] https://github.com/200ok-ch/organice

[1] https://github.com/200ok-ch/org-parser/blob/master/resources...

[2] https://github.com/kristijanhusak/orgmode.nvim/issues/31#iss...