It surely is nice to be able to chat with friends during working hours. However, it seems, that this is a big source of distraction, which is unwanted in an efficient working environment. Unless of course your friends are working on the same project or you are free to discuss work details with friends outside of the project or employer. Many people are not free to do so. Many people have come to realize, that they focus best, when not distracting themselves with friends and family business while at work.
While many people shift effortlessly between async anc sync communication, many people also have problems with that. When you do not respond in time, they get impatient. Some people are seemingly not able to do this shifting as effortlessly.
Just a few points to consider, before getting to any conclusions.