There is no "transfer" of anything. Anyone can edit the root.zone file. I use my own curated version. Great for blocking ads, etc. But for many years no one did this, except very rarely. And the honors were left to some folks in the US, IANA/ICANN. Do not be fooled by the acronyms and the fabricated processes and formalities on the official websites. IANA was essentially one person. Bless the hearts of those who work…
For instance, I'd love it if this recent TLD vomit could be nipped in the bud by people choosing to run their own root.zone. But as it stands doing so myself would merely inconvenience me. And this herd effect is magnified further because the custom is for ISPs to run recursive resolvers for their customers.