At the moment, the only fully supported language, and the de-facto standard for DOM tree manipulation in the browser is JavaScript. It looks like it has deep design issues t
JavaScript is the English language of the web. English historically spread because it had a strong navy conquering various countries. This is comparable to big companies that conquered the web with JavaScript. It's a language clobbered together from multiple European sources (Greek, Latin, Germanic languages, French even some Chinese and Indian words). JavaScript borrowed a lot of concepts throughout the years from other languages (structural, OO, functional). English is spoken in different places with slight variations in dialect and accent, that can render understanding difficult. Just like JavaScript has different browsers interpreting it a bit differently.
Even though English is easy to learn initially, it has very inconsistent pronunciation and more exceptions than rules. Just like JavaScript it's always there to offer a surprise.
Despite the different accents, JavaScript is the lingua franca of the web. Just like you might not be English and write here in English, every web browser has a certain degree of English understanding. IE6 is like the guy who says on his resume that he's fluent, but only went to a two week course on English as a foreign language.
There have been attempts to supplant English as the worlds main language, e.g. Esperanto. But all of them failed, because most people on earth speak some English. In the same way it will be difficult to introduce better alternatives to JavaScript.