Your link  referred to a post which specifically said: "Last month, without warning, Facebook and Twitter killed-off access to RSS feeds. With the launch of the new Twitter interface, you could only access RSS feeds on Twitter if you were logged out of your account. Now, it seems you can’t access them at all. [... followed by a work around ...]"
Furthermore, it then goes on to say: "The process doesn’t work in all instances. Google Reader was unable to recognize the RSS feed." But this isn't a true statement, so now the information is actually misleading.
That seems to echo what I've been saying as well. There used to be an obvious way using established practices to access Twitter via RSS that was auto-discoverable by RSS clients and Web browsers. Now there is not. Judging by the number of RSS-related comments generated in this thread alone, it seems like a legitimate gripe, particularly since adding a simple meta tag isn't exactly an onerous burden.
However, I imagine with the advent of the thin-client AJAXification of the entire site, they don't dynamically create meta tags for this purpose (indeed, I'm not even sure if browsers would support this).