While in theory I don't mind the idea of a .js TLD... This is a can of worms. Just think about all the other programming languages out there and how many other hackers for those would want their own TLD. Then let's expand that out for basically anything else. The question becomes - where do we stop?
We're way beyond that point. ICANN already allows effectively unlimited TLDs as long as they're three letters or longer. So far, thousands of new TLDs have been applied for.
You're right. We already have started sliding down the slippery slope. So I guess the question is... Should we dig in our heels, or just ride it and see where it takes us?
It's certainly an interesting question. One I'm not qualified to answer.
If this is a hobbyist thing, as the letter says, then why not act like hobbyists? ICANN is primarily focused on domain names for profit. It's a business.
Here's how to set up your hobbyist .js TLD. First, run your own mirror copy of the internic root and add an entry for your authoritative .js server. Second, run a recursive server and prime it with your enhanced copy of the internic root. Finally, tell .js fans the IP of your recursive server. Voila, a new TLD for anyone that wants to use it. .js fans that want to use the TLD simply need to change their DNS settings to use your recursive server. The .js fans still get all the same TLD's everyone accepts as "ICANN-approved", plus they get the .js TLD. For those who don't want anything to do with this TLD (and prefer to endorse the ICANN protection racket approach to new gTLD's), this affects nothing. Unless they change their own DNS settings to use your recursive server, they will never see the .js domain. All clean. Zero pollution.