I'm curious whether you or @BlueMonday1984@awful.systems are familiar with the concept of MINASWAN. The only time it's appeared in the discussion is in one of the apologies posted by one of the Ruby Central board members, as their signoff line. Quoting a 2016 analysis of MINASWAN in which it is argued that Ruby's central tenet is not MINASWAN, but wa (和):

Just for the record, MINASWAN is at least half true. Matz is nice. … I would not call DHH nice. … So if MINASWAN is really a basic truth about the Ruby culture, then how does DHH fit in at all? … MINASWAN is garbage. It'd be more accurate to say, "Ruby showcases the Japanese value of 和, but we are arrogant Americans, so we reduce this to a really basic American idea, harshly compressing it in the process to a state where it cannot possibly mean anything any more, instead of bothering to learn something about the outside world for once." But MINASWAN was already a long acronym, so I guess they had to draw the line at RSTJVO和BWAAASWRTTARBAIHCIITPTASWICPMAAMIOBTLSATOWFO.

Also, I really think it's worth understanding that Ruby is not at risk here. Ever since the release of RPG Maker XP in 2005, Ruby has been a staple of embedded scripting for game engines. Really, what we're seeing here is the demise of Rails.

Does ruby just die now?

Part of the background to this issue is the development of rv which apparently offers a future where rubygems is much less important, and some folk seem to be taking that as a threat.

Whether or not the new tooling delivers, the rubygems debacle has probably helped the new project considerably.

Who’s left to do actual work? Who would start a new project that depends on these institutions? Does ruby just die now?

Honestly, it probably will. The RubyGems takeover shattered any trust people had in the Ruby ecosystem - that's something which is damn-nigh impossible to recover from.