Earlier quoted context omitted.
Libera.Chat is likely owned by the Swedish Non profit. The Icelandic entity you see in the whois is the privacy protection of "with held for privacy"[0], a privacy DNS entity. The Swedish non-profit is still in bureaucracy approval from what I've heard from their staff, but you can already look at their bylaws[1]. [0]: https://withheldforprivacy.com [1]: https://libera.chat/bylaws
That is simply an assumption. It is not clear who the owner is exactly because of this "privacy protection". Why does a nonprofit organisation need this privacy protection? The org is the identity that should control it, and the information of the org is a matter of public knowledge (if it REALLY exists, which isnt clear either.) These issues are critical for the trust that the libera.chat domain isn't suddenly going…
The owner are the members of the organization. Look up what an Ideell Förening is.