Sura pretty much encompassed everything I'm about to say, but I still feel a need to speak my mind and experiences either way.
When I first joined this game, I was not in any way new to roleplaying. I'd done it for a while and while I was not what many would consider "illiterate", I certainly didn't have the skills back then as I do today. Some of the best experiences I've had in this game were back then. I didn't frequent the forum at all until I returned to the game under the name Twee, having previously discarded my account due to the lack of time I had back then.
Some of the worst experiences I have had have been when I WAS "literate" enough to join some of the more long-term groups (still being before I became Twee). I am in no way, shape or form active enough anymore for the sort of groups I joined often back then, but at the time, I came online a lot, I had a fair few friends and I was pretty happy. All my "literate" friends, however, tended to shun and bash my "illiterate" ones who sometimes popped over to say hello, provided we were in one of the public maps at the time, usually Fluorite.
It was incredibly unfair to witness and while I am guilty of ignoring people who roleplay with me sometimes in the past, I'm sorry, but nobody deserves to be bullied. Everyone has to start somewhere, and you don't know whether that person is just young and inexperienced, or even has something like dyslexia. You just don't know, and while things said over the Internet should always be taken with a pinch of salt, you don't know their situation or if what you say to them will affect them adversely in some way.
Furthermore, it's just wrong. They generally do nothing wrong to people and those who look down on them tend to be incredibly snobbish about it from my personal experience, and are the kind of people that, again, personally, I have never been able to stay friends with. The strongest bonds I've ever made have rarely been with other "literate" people.
In addition, I really think these terms should be phased out. Why can't we just say "experienced" for a start? It would be much less insulting, and as Sura mentioned, would be far more accurate a word to use. "Literate", "illiterate", these are ridiculous notions. Anyone who calls a less experienced roleplayer "illiterate" is essentially likening them to someone who cannot read or write at all, which just isn't true.
That's really all I have to say on the matter. I don't mean to be insulting, and if it comes across that way, I apologise - this is just a topic I feel quite strongly about.