Am I missing something here? What license is the Matrix Specification itself under? (I know most of the implementations themselves are ASLv2).

It seems really unclear from the site & repo: https://github.com/matrix-org/matrix-doc, https://matrix.org/docs/spec/ (apart from being copyright to Matrix.org)

Is this yet to be clarified? (Maybe the Google vs. Oracle case makes it slightly less relevant, but needs to be clarified).

What stops Matrix getting everyone aboard, then releasing new CLOSED versions of the major server and clients with a new spec (as the protocol formerly known as Axltl did), and carrying the critical mass of user base with them? Sure, the implementations are ASLv2, so in theory the community could fork, but in practice that doesn't always work. Is there going to be incentive to keep it open? (Signal was an 'open' implementation and spec too, but that didn't work out as people expected, even though OWS are non-profit).

Thanks.