Should we design for iffy internet?

Summary

Should we design for iffy internet?Brian Hicks, June 16, 2025I keep hearing claims like this:Not everyone in the US has access to stable, reliable internet, even in 2025.Web developers should stop assuming people have fast internet connections and slim their payloads accordingly.This seems intuitively true to me—programmers are gonna have better connectivity because that takes money, and programmers are well-paid. But what's the actual scope of the problem?I dug around, and here's some data. My goal here is not to beat anyone over the head with "THOU SHALT NOT ASSUME GOOD INTERNET" but to give an idea about the scope of broadband rollout in the US in a way that can help inform choices we make when designing software.If you don't feel like reading this whole thing, here's the bottom line up front: you can probably assume internet access in somewhere around 97% of US households, but you should not assume that it's better than around 25Mbps down and 3Mbps up, and latency may be significantly worse than you previously assumed. This is likely worse for B2C software than B2B.I'm going to pull from two US government agencies here: the Federal Communications Commission (FCC)and the National Center for Education Statistics (NCES) (part of the Department of Education.) All the data I'm referencing was published well before the current administration started gutting the bureaucracy, so I think it's fairly reliable.AssumptionsBefore we begin, there are a bunch of ways to define "stable" or "reliable" internet connections. For the purposes of this post, I'm defining that as a terrestrial link with at least 25Mbps down and 3Mbps up.Terrestrial because—well, have you ever tried to use a satellite connection for anything real? Latency is awful, and the systems tend to go down in bad weather. They also have had fairly low data caps historically so you had to use your connection judiciously, although this may be changing.25/3Mpbs because that's a fairly common cable package speed, an...