Exactly. I get the feeling that a lot of the grinding reactions to this article in the comments here are from people who never lived in the IRC days, or chatted with their friends on AIM, MSN messenger, etc. Not everything is an email, and young people have found ways to convey subtext in shared digital superset of English, nothing wrong with that.

I used IRC. I always capitalized.

Same. Also same experience for me on ICQ, AIM, and Yahoo.

Not everyone follows the "netiquette" though. That doesn't mean it doesn't exist.

Most of these rules rang very true to me at least. For example, capitalizing letters in _informal_ chats does give off a formal tone. This doesn't mean no one does it, but it's definitely a thing.