If I were just out riding on a regular bicycle, I would be very happy with just the simple minimalist data display. But I'm riding a machine that uses a fairly complex, highly variable in terms of quality, and most important...EXPENSIVE...battery technology.
The extra data allow me to better determine if the battery or bicycle motor subsystem, and even the charger is experiencing high stress or problems. The same data can help me determine if battery LIFE is degrading prematurely and even by how much. Such factors can't be determined reliably with just approximate "percent charge" (+/- 25% or 20%), speed, and distance.
Lithium cells can be severely degraded by heat, freezing, too rapid charging, overcharge, overdischarge, and more. Hard riding degrades them more than light riding, so riding style also affects battery life.
Lithium cells also don't like to be left unused in storage for any length of time and I would prefer not to have a $300 exta battery pack sitting around not being required "just in case" my installed battery unexpectedly fails. Proper storage protocols can help mitigate cell degradation, but not eliminate it. Data which can help me detect potential or imminent problems with the battery pack or the motor subsystem (like a malfunctioning or poorly programmed controller that permits overdischarging the battery even fractionally) help me save money by letting me predict when I will need a new battery or motor subsystem evaluation, or even if I ought to change my riding habits if I'm using the bike just for routine riding. For example, the added data can be considered similar to automotive gauges (like a vacuum gauge which lets you know if you're too heavy footed on the gas pedal on carbureted cars or there is a vacuum line leak). Not everyone wants the data, but many do because it helps them save money and possibly avoid being unexpectedly stranded by pointing out when maintenance is advisable.
A car with just a "Check Engine" light generally only tells you when something serious has already happened and requires immediate service...and can even stop the car or prevent it from starting. Whereas, a car with detailed instrumentation can give you warning long before a problem gets that serious.
Most of the "data" you brought up would be better addressed with an advanced charger. Do some research on amp/hrs and you'll find out it's a variable that changes with the age of the battery so unless the the controller on the bike is literally communicating with the charger on amp/hr in and somehow knows exactly how many amp/hrs are remaining each charge then you can't display an accurate capacity remaining and I'm not even explaining this well. It's not like a gas gauge but some think it is.
A bike is also a bit different than a car in that if my battery fails I just have to complete the rest of the ride without assist - I'm not stranded. You might feel you'll sleep better at night knowing all those parameters will be displayed on your ebike LCD but in reality it's mostly just flashy stuff for people still impressed by stuff like that.