Thanks for your interesting response. Although I don't really want to admit it, you are right in some cases that "standards are an expensive detour", because I've been involved with one of those myself! On the other hand, when the object of standardisation is very clearly defined, eminently possible and widely usable, a consensus-backed standard can be made very rapidly indeed.
Data canonicalisation is one such example: although the idea has been around for quite a while, a couple of years ago lots of people spontaneously decided it was something they needed (myself included!), and here we are with RDF canonicalisation[1] nearing Candidate Recommendation not even halfway through its WG's charter, along with several mutually independent approaches also in a good state of development. The result of this is that in about one more year from now, software developers will find cryptographic verification of data considerably more consistent, which can be translated into a pretty significant boon for Web users.
The ideal timing of a standard is surely after the limits of the idea have been found by theorising or prototyping, and before anyone with that idea has a large enough commercial interest in it to benefit from a monopoly on it. Trying to build a monopoly first and then 'donating' it by spearheading a standard is a viable technique, but it feels risky to me unless you can be sure that you're really the only party who understands the idea, and so won't be overtaken by someone with equally monopolistic but less altruistic motives.
I think that a good place to start is limiting the scope of a proposed standard very consciously, unless as you say you have the funds to hire everyone you need to implement it entirely at least once. Although I'm not familiar enough with your project to comment on any details, I suspect that most social network or forum applications could implement one way ActivityPub or Matrix support easily, and also proper two-way federation unless the original software makes too many assumptions about identity.
[1]: https://www.w3.org/TR/rdf-canon/