There are fields I have been interested in that weren’t in the export (as of ±1-2 yr. ago). I assumed it was intentional and not a bug, but never checked further. The availability of exports became Admin-only, and no longer having real data to work with difficulty increased, interest waned, and a few heavy doses of RL ended that path.
Without looking a wild guess is that if not changed in core, a plugin could easily get values from tables and add them to the CSV export. But I think the Data Explorer plugin is a good candidate for a custom export.
My current interest for the most part has since moved from hacking of Admin-only core files to putting together bespoke userscripts.
Maybe with enough consensus the current export can be changed?