If you're just slinging static HTML, there's really not that big of a difference, and if it's a frequently accessed resource where a difference might be expected to matter, it will be cached regardless.
Hilariously enough, that's no longer true in many parts of the world; according to firefox telemetry, on-device storage is frequently much slower than the network.
Do you happen to have a link for that? It seems pretty counterintuitive given the state of modern PC hardware.