It's helpful, but even after all the work to be on all the right levels one still has a difficult prediction problem to decide when they don't like a fill. I guess the point is that this prediction problem (conditional on fills at front of big queues, should I dump it?) may be easier to make into a profit because your predictions can be of only moderate quality if your downside is just fees. In crypto d1, the fees are maybe small enough to support this, but other concerns make it difficult. As mentioned elsewhere in the comment section, one may learn that their downside is often not just fees.
Yeah, totally, it really just gives a flavour of how the structure of price levels and price/time priority, tick sizes, etc. can create exploitable probabilistic advantages, and I think many folk are not aware of even this.
The real environment is absolutely messier and more complex than described by this article. Still, it's a layer deeper than "speed is good", to paraphrase Gordon Gekko.
