To be honest, this is the only reason why I still have Twitter. I use it to contact various companies and ask for tech support. If I can't do that now, then there's no point to keep the account alive. Self-proclaimed genius is kind of an idiot. Just recently he complained about 50% drop rate in ad revenue, after killing ability to view tweets without account.
It is not meant for companies and companies who regularly talk to customers on twitter will definitely turn this feature off. So you will likely still be able to talk with any company that wants to talk with its customers on twitter.
It is meant for regular folks who get lot of unsolicited spam in their inboxes. It puts an immediate stop to those. So in that sense, it’s a tricky but good move.
They don’t need a blue thing just to talk. They can just turn the feature off and they will be available to receive messages again from their customers. It’s just as simple as it was earlier to keep your messages open or closed to general public.