I think it's a little ironic that someone who hasn't seemed to have committed to the codebase of irssi for years has decided to come in and put their foot down in such an aggressive way. Funny, I feel like I JUST saw something like this happen somewhere else...
It's quite concerning that ailin-nemui, who made the prior commit migrating to Libera currently isn't listed as part of the irssi organization[1]. According to GitHub stats, this is the person behind most of the code in irssi[2]. [1]: https://github.com/orgs/irssi/people [2]: https://github.com/irssi/irssi/graphs/contributors
In all likelihood, they probably just had their commit access revoked, or are just hiding their membership as part of the organization.