> Having a ledger that is secured by decentralised consensus is not only useful but will be a necessity for the digital first future we are heading towards.

I think I would disagree with this specifically; at least I would disagree that blockchain ledgers are necessary or helpful in most situations.

I'm not going to say that there's no applications that are useful that would rely on a blockchain, but they're extremely limited and the technology itself seemed to be mostly useful and mostly oriented towards turning plentiful resources into scarce ones.

It's of course bad for Meta to be the arbiter of consensus. It doesn't necessarily follow that distributed (in some ways still very centralized, at least on a conceptual level) ledgers are a good alternative, particularly now that we're seeing that basing consensus around eventual consistency, fragmentation, etc... seems to be at least more promising than the alternatives, even if it isn't perfect.

I'm very much in support of efforts like 3rd Room, Fediverse, Matrix -- seeing their success has given me very little reason to believe that distributed ledgers would be necessary, and has given me some reason to believe that in many instances they would be actively harmful. 3rd Room for example would (imo) absolutely be a worse project if it was economically/socially built around a distributed ledger. Not only is there no need for 3rd Room to have that kind of coordination around state in VR rooms, it would be actually harmful for 3rd Room to require all of its VR rooms to use a shared ledger/state. Consensus (distributed or not) isn't necessary for what they're trying to build.