I think you need to read their reply more carefully, because when I read:

> We will only store the actual requests that are sent when the user signs into the application.

It seems obvious to me that they are talking about your request that results from you logging into your postman account, that's why they say:

> If you do not create an account or use Postman without signing in then we will not collect any of the data

They are NOT saying "we record every REST request you generate from postman and send it to our servers".