There aren't millions of pubky nodes, pubky has no concept of nodes. Pubky uses pkarr.org, which is just a spec for using Mainline (Bittorrent) DHT and especially BEP0044 to publish DNS packets.

According to Pkarr, public keys ARE the TLD. Controversial design decision I know, but I stand by it. So no plans to beg ICANN for a TLD. Gnunet begged for .gnu and ICANN refused. We need them even less, given that we use 52 characters TLDs, there will never be a collision with ICANN tlds.