There has been a lot of talk about Twitter's vague plan to decentralize over the next few years. I think this is actually a response to the possibility of regulation by governments.
They will have whiteboarded the possible regulation scenarios. One would be "broken up/antitrust" another would have been "mandatory open protocol/standards enforcement". In this fictional meeting the CEO would have asked "ok, so how do we survive as a company in these scenarios? Something like this is coming, so can we get out ahead of it?".
If they're going to be required to support a standard protocol then it's obviously in Twitter's favour to be the one defining that protocol. If they've figured things out well in advance then they have a negotiating position when the government regulations are hammered out some years in the future. If they have no negotiating position then something will be imposed upon them which might not fit the business model so well...like ActivityPub.
So what's being proposed is really a hedge against a certain kind of regulation. They can easily afford to put a few engineers onto it, and if the scenario never happens then it's no great loss to them.