Do you want linear braking torque though? Progressive (more speed-more torque) braking may help to brake to exact spot and avoid lockup.
As you brake, car dives in, taking force off rear wheels. With linear braking, it may be too easy to lock them up. Which is especially dangerous if you're still braking when entering the corner.
"Torque increases linearly with speed" means "more speed more torque".
The "linear braking torque" you are talking about seems to be a completely unrelated concept referring to how the brakes react to inputs from the pedal. A braking system can have both of those, none, or any single one.
That said, there are many practical limitations that may apply.