Has anyone tried using the relatively new features for "tagging" - that allows one to indicate the structure of the document: https://en.wikipedia.org/wiki/PDF

Has anyone tried using the relatively new features for "tagging" - that allows one to indicate the structure of the document: https://en.wikipedia.org/wiki/PDF#Logical_structure_and_accessibility https://en.wikipedia.org/wiki/PDF#Logical_structure_and_acce... ? Wondering if these are usable and how far they go to fixing the problem?