Earlier quoted context omitted.
The thrust reversers are more than just an assist on the runway. You can land without the reversers, but I'm pretty sure you'll have to go get the brakes replaced before it's ready to fly again. It'll also consume a dangerous amount of the runway. The reversers are no joke, especially when the aircraft is heavily laden.
An aircraft operating nominally is designed and intended to be able to land safely relying on just the brakes. Thrust reversers are also used because they decelerate the aircraft quicker and with less wear on the brakes, aka thrust reversers are used out of convenience and benefits. Thrust reversers may be used solely in an emergency that renders the brakes inoperable, but such situations are so exceptional they aren…
Yes. That doesn't contradict what I wrote.
The thrust reversers also greatly reduce the stress on the tires, another critical and expensive item. There's also the enormous heat generated, which stresses the rest of the landing gear and the bearings.
One of the certification tests is the airliner is landed with flaps up, at max landing weight, and no thrust reversers.
The tires inevitably blow and catch fire, and the airplane literally grinds to a halt, with a raging fire on each truck. The firemen have to wait a specified amount of time before they can put the fire out.
While this is "landing safely", at minimum the landing gear is wrecked, and I suppose some of the fuselage panels.
The thrust reversers are an expensive piece of machinery, with a lot of engineering expended on them. They are not a "would be nice if" piece of equipment. The brakes are a backup system for the thrust reversers, not the other way around.