Twitter already said that most people access Twitter through their web ui and mobile apps. So even if they were shutting their whole API down, it wouldn't have such a negative effect on their usage growth. The only thing that's happening is that devs won't be able to build toys around Twitter, but Twitter doesn't care as most people don't use nor need these toys.
Some of us devs just have to admit that we are not that important to the success of Twitter, at least, not anymore. It's also not a charity so they need to make money somewhere, I don't really see the problem here.
"Twitter already said that most people access Twitter through their web ui and mobile apps."
My problem with this stance is the same problem I have with so called "browser share".
I am not beholden to a single interface. I'm human. I'm dynamic. I move and change.
That means sometimes I use the website. Sometimes I use the mobile app. Sometimes I embed Tweets on a website. Sometimes I use a website's embedded tweets to follow them instead of following them on Twitter. I send photos and tweets from apps, and I consume tweets from multiple sources.
Twitter is almost as ubiquitous as water for me, the ways I consume and use it in my day to day. There is no single one size fits all interface to Twitter in my workflow, only Twitter the service. Because if there were, if I had to go to the website and only the website, or the app and only the app, I wouldn't use it. I don't use things that get in my way. You either fit into my workflow, or you don't.
And I'll miss the Mac OS desktop client if the rumors are true, because the website doesn't have a simple way to switch between multiple Twitter identities if I'm running a personal Twitter, a brand Twitter. And also because they bought Tweetie only to, eventually, kill it. But we've had this discussion before.
Does anyone know the actual percentage of users that access Twitter through third party client applications? And what users are currently getting out of these apps that would make them annoyed enough to quit the service if they were forced to switch to Twitter's app/web interface?
My gut reaction is to agree with you that the Hacker community is overreacting to getting screwed over and that Twitter will go on fine without us. But without any facts about how popular and widely used these third party apps are, my opinion is really just a guess.
This is just my own testimony, but there are numerous features in tweet bot which Twitters own app doesn't even attempt to provide. Such as conversation threading in both directions (twitter only let's you see In Reply To). The app is also quite a bit more polished and better behaved (Twitter Mac triggers my discrete gpu, Tweetbot doesn't). Twitter Mac doesn't even support gestures.
As for the website... Twitter loses all its value to me if I have to open a browser every time I want to read content.
Some of us devs just have to admit that we are not that important to the success of Twitter, at least, not anymore. It's also not a charity so they need to make money somewhere, I don't really see the problem here.