[t0mas88]

This already exists and in a much more advanced way. The flight management system calculates the expected fuel on landing based on the route, wind data, different fuel usage at altitudes etc.

It's not as simple as "fuel per time" because fuel usage and speed change massively with altitude.

What was missing here was a big warning to the pilots (that has since been added). But it's also standard procedure at all airlines to monitor fuel and required fuel calculations, which could have helped this crew if they did it earlier.