Will Mastodon eventually end up centralizing like email?

In 2022, it’s almost impossible to run your own email server and actually have your emails be treated as non-spam by people you want to send email to. I fear Mastodon’s model may eventually suffer from the same dynamics.

Mastodon’s federation model assumes that bad actors will be pushed out because instances will be incentivized to keep effective moderation or face being block listed from other meaningful instances.

One oblivious class of bad actors are spammers. In email it played out that Google’s Gmail, due to its centralization and scale had the best spam detection. And thanks to their ad supported model, they had the largest user base creating a feedback loop leading to enrichment.

As spammers got more sophisticated, the trust needed to convince an e-mail provider not to route your email directly to spam moved from technical tools (certificates etc) to more reputational. Are you one of the big players?

I wonder how Mastodon will avoid the same fate. Will spam avoidance lead to the largest instances being best positioned to suppress spam? Will this lead to consolidation of instances? Will that lead to a closed group of trusted instances? Will they necessarily be so large that they will be beholden to regulators and share holders?

I don’t love that outcome compared to what I see in the Mastodon ecosystem today. But I think I still like it better than truly centralized social media like we have today.