Because many people seem to be misinterpreting Namecoin's role, I'll quote the source:
The ICANN community appears to be reasonably accepting of Namecoins role as an alternative to DNS; Namecoin makes different tradeoffs from DNS, is therefore likely to be optimal for a different userbase, and can co-exist with DNS in its current state.
https://namecoin.org/2017/04/17/icann-58-summary.htmlThis means that ICANN recognizes Namecoin as an alternative and doesn't want to interfere. The developers would like to avoid a "collision" that'd cause .bit ending up becoming an ICANN TLD.