@pmdj @gsuberland Which interestingly I sometimes find pretty old echoes to this idea.

Like Benjamin Bayart in 2004 expressed it with https://edgard.fdn.fr/liberateur/ (in french).
With taking the example of how OpenOffice.Org would effectively not interoperate with other software. It's a bit better nowadays but, let's face it, if you get an odt file, you're going to use LibreOffice or might have to ask for a PDF. Because KOffice or AbiWord won't properly render the document.

And kind of wonder since when Cory Doctorow spoke about interoperability.