He didn't run the Memgraph one, only took their numbers https://news.ycombinator.com/item?id=34368362

I'd assume it's what the disclaimer at the top was about: that the code is in Python which he's not familiar enough with. The license bit on not having the right to integrate it if you're building a competing product might not be decisive but a good enough reason to not invest more time into running the code.