I grabbed the source linked from the article, made it run on Linux, compiled it with gcc -O3, and it beats my system's wc by a factor of almost 2x. C is faster than C!

System wc, fastest of 5 runs:

      59180000  213180000 1407437834 wc_input
    11.53user 0.19system 0:11.74elapsed 99%CPU (0avgtext+0avgdata 2428maxresident)k
    0inputs+0outputs (0major+102minor)pagefaults 0swaps

Manually compiled wc, fastest of 5 runs:

     59180000 213180000 1407437834 wc_input
    6.08user 0.20system 0:06.29elapsed 99%CPU (0avgtext+0avgdata 2180maxresident)k
    0inputs+0outputs (0major+92minor)pagefaults 0swaps

This is on Ubuntu 18.04 on x86_64. If the author's wc also came precompiled (which it seems to be), they cannot make any valid comparison at all. If manually compiling on their machine with maximum optimization would also get them a 2x speedup, their fancy multicore Haskell would still be slower than C... and that's fine.