They might have a decent power band, but you have to get it there, so a car that weighs 1700kgs has to have some bottom end torque to be able to pull it to the power band (think of a 2-stroke single cylinder race bike, horrible slow until they are in the right rev range), where then it would take off, so while it would be quick while in the power band (which doesnt start to about 10000rpm) it has to get there in the 1st place and would be rather slow untill it did.
My example is then a Diesel Le mans prototype, they only rev to 5500 but are still plenty quick, dont make a heap of power but have a stupid amount of torque, as you say they are geared for it.
No point in having an engine that revs to 17,200 like an f1 car if you have to anything other than drive for 300km in a 600kg car with more aero aids than an F-117