Not sure why there is so much hate on this thread. I found the post well written, insightful, and pragmatic.

Having built systems that process billions of events and displayed results, triggered notifications, etc in real time (not RTOS level, I'm talking 1 or 2 seconds of latency) you absolutely need to separate reads and writes. And if you can trust db replication to be fast and reliable, you can indeed skip distributed locks and stay on the right side of the CAP theorem.

Event sourcing is how every write ahead log works. Which powers basically every db.

Is the concern on this thread that they preoptimized? I thought they walked through their decision making process pretty clearly.