Apple should have added a Amp or Watt usage number, not removed the estimate. Similarly, most new cars have fuel estimates on their dashboards. But its not just miles to empty, its also miles per gallon. So drivers can get feedback on usage rates versus total capacity.
I imagine the argument about this, is that most people don't have any handle on what a Watt or mAh is. But people don't have a good handle on how far 25 miles is, or how much a gallon is in comparison to their tank. Think about it, you rarely see the fuel you put into your car beyond a few drips at the pump. And while you may know that its 25 miles between your house in work, if I took a random point on a map and said find something 25 miles away, with no scale, most people couldn't do it. Gallons and MPG are just arbitrary numbers that consumers have learned how to compare. If you exposed those numbers, they would get a better handling on what their device consumes, and how their activities affect it.
I imagine the argument about this, is that most people don't have any handle on what a Watt or mAh is. But people don't have a good handle on how far 25 miles is, or how much a gallon is in comparison to their tank. Think about it, you rarely see the fuel you put into your car beyond a few drips at the pump. And while you may know that its 25 miles between your house in work, if I took a random point on a map and said find something 25 miles away, with no scale, most people couldn't do it. Gallons and MPG are just arbitrary numbers that consumers have learned how to compare. If you exposed those numbers, they would get a better handling on what their device consumes, and how their activities affect it.