[James_K]

I think the problem with emaill is more the availability of it. Anyone can send you an email so they mostly wind up as junk that needs to be managed.

[ejoso]

One of the most significant problems, agreed.

Also, email is free to the sender but costly (in time) to the recipient. This is reflected in the quantity of messages, but also in their verbosity. People rarely expend the effort to edit or be concise. Both are costly to readers.