The 10x claim reminds me of various scaling laws in anthropology/sociology, especially the much-debated Haire cube-root scaling law (eg https://gwern.net/doc/sociology/1959-haire.pdf https://gwern.net/doc/economics/1983-stephan.pdf ). I wonder if one could give a derivation from queuing theory where you have an argument along the lines of 'in indefinitely many layers of queues of queues, the total delay is minimized at 90% load per queue which yields a 10x scale-free slowdown'?