I'm sure this has been done elsewhere on the net, for sure at other carriers.
To me, as a regular user of my cellular device, over the last 4 years, I know what I use, and rarely do I have an issue with overages (on other carriers). I am the best predictor of my data requirement, and no one's prediction tool will ever get it right.
Stream music at low, high or superbeefed up top quality, same for video. How many emails do I get, do I tether my laptop to the phone's hotspot?
Personal experience is the best way to estimate. Sometimes, you just have to limit yourself, or pay for what you want.
It is impossible for a carrier to tell a prospective customer what kind of plan they need based on their past usage profile. As a shopper, you need to go shopping with the "grocery list in hand. The carrier's job is to have a good selection to best match anticipated needed.
