Thanks for sharing. Would recommend switching to a consistent throughput unit to save on the reader's mental bandwidth.
The article switches anywhere from Billion / day as the title to per minute (when talking about feature store ingestion) to per second (write capacity units).
This makes it hard to grasp the impact. 1 Billion per day sounds like a lot (probably to garner readers' attention), but if you put it simply, it's just 270 K messages/sec. Otherwise, might as well say "How we process 1/3 trillion messages a year"
Having one standardised unit would help in improving the effectiveness of the changes you highlight.