(1) Interesting that this is presented as a webpage instead of a normal paper on eprint or arxiv.

(2) If Mike Hamburg is behind it (no author information is available on the page), then it has high credibility.

I would take objection to the following statement: "However, modern elliptic curve implementations with fast, simple formulas don't provide a prime-order group."

The Broker-Stevanhagen (and prior) methods can find good curves with prime order, and complete formulas for these curves that are reasonably efficient are given by Renes, Costello, and Batina in https://eprint.iacr.org/2015/1060

So this performance knife-fight in the ellpitic curve streets may require some benchmarks to resolve.