Okay why are we still using a centralized domain name system with authorities? Do we enjoy the crazy keyholders from various countries meeting in secret thing?
We can have many decentralized ways of registering and transferring domains. Namecoin is one, but how hard is it to decentralize the DNS database?
Alternative DNS roots exist [1] but they're not going to receive widespread adoption as the current system is deeply ingrained into how the Internet works, and works well enough. Even if it was massively flawed, people would still be unlikely to change to something new in a timely manner due to network effect - just look at the poor adoption rate of IPv6 despite IPv4's inadequacies. Or our continued reliance on SMTP with all its problems.
To honestly answer your question: the we you refer to isn't in control / power.
The system is centralized because the control over nations is centralized. It will remain that way so long as political power remains centralized. Particularly given the immense importance of the internet economy now to most major nations. The political powers that be are not about to let go of something so important. The domain name system is a huge point of control over national and global economics. If I were a standard issue politician, I'd make you pry it from my cold dead hands.
What is to prevent an open source DNS server to be deployed all around the world by various people? And browser makers would just add it to the list of servers once it gets big enough.
Until then, people could download a program or instructions that would add it, similarly to Google's DNS or OpenDNS
Except it would not use the regular DNS system on the back end, but supplement it with its own rules eg not taking a domain offline when registrars do.
Namecoin is a stupid idea, as many/most people can't participate, only people with botnets or dedicated mining hardware.
Alternate DNS roots are just scams, as the intention is to extract more money so people have to protect their name by not only buying many TLDs in the real DNS, but in an extra one as well.
We can have many decentralized ways of registering and transferring domains. Namecoin is one, but how hard is it to decentralize the DNS database?