I guess there is a convergence of ideas going on here because I've actually been tinkering on something like this, a Notion-database-like that just uses flat CSV files (and internally reads it into an in-memory SQLite for filtering, grouping and displaying) then schema files for interpreting the data and displaying it nicely.

Here's a little demo of what I've got working: https://youtu.be/LCR9pAc_xn0.

It's currently still very rough and I'm just using it myself but hoping to open source it at some point.