I see what you mean with the first. The interop fediverse <----> solid is further removed from the primary focus in that regard (and it is something the community can investigate). But other non-solid developments are ‘closer to home’ and may become part of the activity. I will name three that I’m aware of:
The first two relate to the direction that the Fediverse is trending to (and in both Christopher Lemmer Webber is taking the lead, I believe):
And the other is a Identity Foundation initiative
- Encrypted Data Vaults (original RWOT paper)