CSV / TSV has been an awkward but universal and very flexible format for decades now. W3C _finally_ has figured out a good way to do metadata for CSV.
Honestly, I thought they’d never manage it. I guess it was fun coming up with new standards for new things and big elaborate projects, while people like me who just have to get things done “quick and dirty” keep using CSV and Excel spreadsheets.
I feel strangely validated now.