This reminds me a lot of OpenID over a decade ago. The idea was anyone could setup their own identity provider on their own domain and login anywhere. Unfortunately it became "login with google/facebook" which is a real shame. I hope sites don't restrict ActivityPub usage to only a few big players.
Funny enough, Steam is one of the only big OpenID providers left, it's always fun when something still supports it and I can log into it with my Steam account.
There's been talk about Embrace Extend Extinguish coming to the Fediverse, with the counter-argument that anyone who tried it would find themselves almost universally de-federated and just building their own walled garden.
I actually expect most Masto and PixelFed instances will block Tumblr pretty fast.
This is wishful thinking. People will use whatever is easiest even if it means centralization.
There are two routes we could take to fix this. One is building social pressure and a social consciousness around federation. The other is to bribe people, like how crypto social media rewards people for making popular posts.
I’d posit there’s a generic way to assess the hope:
Does the protocol come with inherently good way to deal with spam right in the core design? If not, it’ll eventually end with delegating trust to corporations.
My usual example to explain the concept of federation to people is email - you create an email account with your preferred provider and they all talk to each other.
It's a good analogy on a couple of levels, because of course Gmail has become a dominant player in that space, in some occasionally problematic ways (e.g. it's very difficult to run your own email server now, because GMail might decide you're not trustworthy and stop delivering your mail). There are still several big players though and the system works.
However centralization is still a theoretical threat, just like it happened with E-Mail or the various services that started as implementations of XMPP.
And an oligopoly is still preferable to a monopoly. It may be unrealistic to run my own email server, but I can use GMail on my domain and if I want to switch to Fastmail, I can do that. If that’s where fediverse ends up, it will still be preferable to what we have today.
How do they deal with Spam? Domains are cheap, someone could just stand up new instances, federate, dump a load of Spam on everyone and not care about their instance being defederated.
Personally, I wouldn't see it because my main timeline is "following only" (I also have a "followers + replies they make" view for finding new content.) Also I'd be able to remove it because I control my server. Also also I could write a Pleroma filter which says "if it's a post to me and I've not seen that instance before, hide it".
As an instance admin since 2017: we don't have a way to fight this, and it just hasn't been an issue yet because spammers are incompetent. They always just sign up with accounts on legit instances.
When competent spammers start looking at Mastodon, either we hope buying domains is too expensive to be worth it (unlike email spam), or rely on IP range bans.
For one, you can't really spam hashtags since there's no global search or timeline. It only shows up for users if someone on their instance follows the spamming account.
Reply spam still works, but that doesn't scale as easily.
This is because people refuse to acknowledge and solve the core issues. Techies think all you need to do is to create a ideologically superior technology and people will gravitate to it over time.
People will gravitate towards whatever is easiest unless incentivized to do otherwise. Usually incentives are either social or financial and interestingly both are being attempted currently.
The left-leaning folks are trying the social pressure route. One of the themes of the modern left is trying to change culture in order to pressure people into doing the right thing. You can see this right now with the vitriol against Elon Musk on twitter. This vitriol creates social pressure.
The libertarian-minded folks are attempting the financial route. One way of viewing crypto is as a tool to bribe people away from traditional institutions. Crypto wallets are essentially bribing people to install cryptographic tools onto their devices. De-fi is trying to lure people away from traditional financial institutions.
How you judge either movement is up to you. I’m just saying what I’ve observed. It’s also worth noting that each movement is creating copies of traditional web apps. There is a crypto version of reddit and a federated version of reddit for example.