Without API we go back to web scraping, Selenium, etc. Now guess which method is more expensive for any company (including Twitter)? Web scraping. Its the entire reason an API started to exist in the first place. Besides, if there is authentication involved, the user is logged in, and API calls can be profiled.
So I would say to your statement: "Definitely not." Only on the short term. And those users you lose you might be able to write off as dead weight or leeches but if a couple of big fish will have impact on the power of the network effect. And once that is reduced, the domino effect might take place.
Without API we go back to web scraping, Selenium, etc. Now guess which method is more expensive for any company (including Twitter)? Web scraping. Its the entire reason an API started to exist in the first place. Besides, if there is authentication involved, the user is logged in, and API calls can be profiled.
So I would say to your statement: "Definitely not." Only on the short term. And those users you lose you might be able to write off as dead weight or leeches but if a couple of big fish will have impact on the power of the network effect. And once that is reduced, the domino effect might take place.