Email is an indispensable tool in the modern offices which require their employees to work on computers for many professions.
Email is a word that literally means electronic mail and now email has replaced the traditional letters between various organizations, persons and family members. Business do send important letters related to contracts where signatures are involved, but otherwise the trend these days is to stick with email, opt to receive bills online, for saving time, energy and environment.
In spite of a tremendous raise of IM (instant messaging) apps because of large number of mobile subscribers, email still has its place on the internet space and it may exist till a new agreed method of credible communication would be invented that could replace email.
In the near future it doesn't seem to be possible.