Author here, I did run it a few times but you don’t have to take my word for it, you can rerun the notebook yourself if you sign up for Nextjournal and remix my notebook. Full disclosure: I’m also a Cofounder of Nextjournal.
But I wouldn’t suggest to use Nextjournal for serious benchmarking (yet). We’re running on Google Cloud and it’s not suited for benchmarking unless you pay for a (big) sole tenant instance. In the future we plan to offer dedicated instances for benchmarking.
I should hope that anyone doing benchmarks does them multiple times to avoid crap like popcon or adobe reader update randomly keeping the system busy during one of the two algorithms' benchmarks. I don't expect that the author ran this only once and decided to make a blog post based on that, even if the post doesn't show multiple runs.