Social media platforms cost money. Until we solve that, without monetizing it and giving rich parasites an advantage, we'll continue to be pitted against each other to there benefit. Fediverse, mastadon, other open source systems are likely the way, but until everyone abandons the fake monetized social media, they'll continue to reign.
Mastodon is a piece of software. mastodon.social is a social media platform, which happens to interoperate with many others, and not with many more. That's important to remember. chaos.social is also a social media platform, which happens to interoperate with many others including mastodon.social.
In the open source world there's this tendency to confuse software and services - people write software with which a service could be run, and then declare that the service exists. Highly P2P software (like Bitcoin) is an exception since the software and the service are basically the same thing.
Services don't have to be expensive to run, but they do if they want to host image and video uploads. IRC is still available for free. The most expensive part of running a service in the current environment is most likely mitigating the legal risk when someone uploads something the government doesn't like. Note this expense doesn't exist if you run it on the dark web, but then you won't have any users either.
I prefer to pay with my wallet than my data, mental health, and time, you can create a good social media site that is subscription based, you can fully monetize it that way, sure many users wouldn't even approach it once they see the word "paid" but you don't need to appeal to everyone, a service being paid makes people consider their choices more carefully.
