The real insight here is recognizing when network latency is your bottleneck. For many workloads, even a mediocre local database beats a great remote one. The question isn't "which database is best" but "does my architecture need to cross network boundaries at all?"
Sure. Now keep everything in memory and use redis or memcache. Easy to get performance if you change the rules.
(author here) yes 100% this. This was never mean't to be a SQLite vs Postgres article per say, more about the fundamental limitations of the network databases in some contexts. Admittedly, at times I felt I struggle to convey this in the article.