Really, do we need to learn reading emails? - Yes. Normally, people read emails for 25% of their workday. So, it make sense to learn how to read and write them in such a way as to keep the discussion concise and responsive.
Few points to understand
It takes some time to read email
Email to be crafted with a list of expectation and responses in mind
Email provides some breathing space for us to think
Emails are not meant for instant communication
We need to thought through the information, do some work and revert back.