Email is great for so many things, but that doesn't make it right for everything. In many cases in business, meeting in person or even a phone call are much better than an email.
It's hard to get to know new people exclusively through email or social media. I know that sometimes my attempts at jokes would come across differently in person than they do reduced to the written word (and I suppose other jokes might work better in written form).
I am pretty sure that I have never sold a new client on my company InfoStrat without at least a series of phone calls, and in nearly every case, in-person meetings.
Hiring, promoting and firing employees is best in person, although distance sometimes create the imperative for an HR phone call. This falls under the same rules about breaking up via text message.
After I know someone, an email can be a great way to provide information quickly. I really appreciate emails with quick status updates, for instance.
So let the medium suit the message, and consider when to use email and when to use a meeting, phone call, or even a text message instead.