You may be interested in the wunderfull Elastic Tabstops concept which although it has proof of concepts and plugins for most editors sadly never got widespread adoption:
That is almost exactly what I was thinking with "dynamic tabs" (just missing a few extra bits that are probably just me overcomplicating things anyway so wouldn't be in any initial PoC). Thanks for the link, I'll investigate further from there.
https://nick-gravgaard.com/elastic-tabstops/