[KirillPanov]

Namecoin failed mainly because it was way, way, way too cheap to register names, so everything got squatted in the first few years.

ENS appears to have fixed this; the registration and renewal fees are denominated in USD (but paid in ETH) and cost about the same ($5/yr) as ICANN names.

Unfortunately ENS has the same problem that a lot of "new crypto" does: the rules can be changed at any time by a tiny handful of (mostly) anonymous people who hold the magic multisig keys to update the special contract. There is no developer/user separation, where the users can simply choose not to upgrade. The ever-present threat of this "declined to upgrade" situation is a major check on the developers' power in bitcoin/namecoin-style cryptocurrencies, and it is the central topic of discussion in any hard fork proposal.