This does not mean that no one talks anymore. Indeed people talk a lot, and when not talking they listen to other people talk. Talking is not the same as conversation. It is easy to talk to someone without entering into a genuine relationship with him or her. Two people can talk at one another and use conversation just to vent their feelings.
People speak to each another for many reasons, and they do many things with the words they speak.
Straightforward communication of information is one of the primary uses of speech. Others are to give commands or make requests. Language is useful in these kinds of speaking. Think of communication in commercial settings where words are spoken and money changes hands. When people don't need to use language to accomplish practical ends, then conversation is possible, as well as idle chat and gossip.