Repeat after me. "It is better to make torque at high rpm than at low rpm, because you can take advantage of *gearing*."

I don't agree totally with that conclusion. It's not that any of the math behind it it is wrong, but more simply that you don't really have much choice in the matter. Your torque and HP curves are somewhat dictated by the bore and stroke of the engine (leave forced induction out of the equation for the moment).
So maybe you take your stock 2.6L engine, and spend a small fortune overboring it and shortening the stroke to shift the torque up the rpm axis. Then you can go and spend another $1k+ on have the tranny dropped to change the gearing to take advantage of it. Great. In the meantime someone comes along with the same car with a stock 3.2L engine in it, and you're stuffed. Or a turboed 2L would also give similar results.

Speaking of turbos, they (and superchargers) are the easiest way to radically shift the torque curve around, assuming that the internals can take it. Basically a larger turbo can provide more torque higher in the rpm range (and peak power is therefore obviously higher)., whereas a smaller turbo provides torque earlier (less lag) but runs out of breath earlier too. Even here I couldn't agree totally with that conclusion - I don't spend my driving life at 5k RPM in 3nd gear. I wouldn't want to. Most of my driving is interstate cruising. Having a hefty punch of torque at cruising RPMs is really useful to me. Why would I want to downshift when I don't have to?

I reckon that for 99% of drivers 99% of the time, torque is more useful lower in the RPM range than higher.

Now if you want to talk specifically about drag racing, or want to discuss maximising racing performance from a given engine size, then I'd happily accept that statement. To be fair to that primer, I believe that it is approaching the subject from a drag racer's perspective. I just don't think it holds up well for the rest of us.