To me, the argument for accepting Meta into the Fediverse goes beyond gain and loss. If you run an Internet service, you have a moral obligation to make a good faith attempt to interoperate with anyone using the protocol as intended.
By a similar token, if you run a mail server, you should accept SMTP connections as far as possible. Yes, you can ban spam, but you should not ban connections from Gmail even if Gmail is a privacy-destroying bad idea. By all means, allow individual users to set up their own block lists, but this should not be done at the server level.
The counter argument is that standardized open protocols are important. So if a big corporation moves to adopt a standardized open protocol, it’s a good thing for everyone, even if said corporation is sketchy, evil, or whatever.
It’s kind of like Microsoft’s adoption of XML for Office save files. Yes, they had ulterior motives, and the result isn’t completely satisfactory for third parties who want to parse the save data. But it’s still miles better than the previous situation where things were completely closed off.
It’s worth mentioning the Interactive Fiction Archive, a massive catalogue of hobbyist-created text games, many based on free text game engines like TADS.
Chrono Trigger. It’s basically the evolutionary peak of the NES-era console RPG. Every aspect, including the story, art, game mechanics, and music, are best-in-class, with no obvious room for improvement given the technical constraints of the time.