I couldn't disagree more with the author. Twitter is what you decide to make it. If you don't like someone's tweets, don't follow them. Make twitter the experience you want it to be.
I'm not sure you finished the piece. The author says this:
Luckily, Twitter has an amazing feature that will
instantly remove negativity from your stream. It's
called UNFOLLOWING. The next time something feels a
bit too snarky: Unfollow that user. Before you know
it, you'll have a really nice place where people have
interesting and quirky conversations.
So you seem to be agreeing with him, not disagreeing.
There's an additional point: People may not realize just how negative the come across on Twitter.
I'm sure some people do, and do so on purpose, and if that's their choice then great. Follow or unfollow.
But if you find yourself turning to Twitter to vent you may not realize that, to many people, all you do is vent and complain. It may only be a small part of your total personality but if that's all you're showing to some people that's what they'll use to judge you.
A corollary to this might be that people should not be so quick to judge others based on some small sampling of their comments or tweets.
There's a very good chance they've said and done much more than what you've just happened to come across on the Intarwebs, and you've only seen a small part of that, and even that has been filtered though specific media and circumstances.
