I don't know how many of you remember the early days of what we then called the "World Wide Web," or before that, online "bulletin boards," but there was a time when the great thing about "chatting" was precisely that you could pretend to be someone you're not. You could try on different identities, and in the process, people learned a lot about themselves and who they wanted to be.
Sometime around 1997, as more people began using the internet, the people who used chat for this kind of self-exploration became outnumbered by the people who used it to try and get laid in real life. For the latter, of course, experimenting with one's identity was a cardinal sin -- self-exploration became "lying about who you are."
It still seems to me that, unless you intend to physically meet the people you chat with online, it shouldn't matter whether they depict themselves accurately. You are interacting with a created character, which is pretty much what you do whenever you read a book or watch a movie.