It would seem to me that open standards are the answer to walled gardens rather than 'Free, open source and federated'. I don't know of any standards-based act

It would seem to me that open standards are the answer to walled gardens rather than 'Free, open source and federated'. I don't know of any standards-based activity discussing a twitter-like capability but multiple interoperable implementations, open and closed source, free and for money, provides an 'ecosystem'. I would contrast an ecosystem to a platform. A platform is owned or controlled centrally whereas a successful ecosystem isn't. A well-managed platform ultimately provides the most benefits to the platform owner whereas a successful ecosystem provides the benefits to the most successful entities within it, a playing field to compete within.