Both the gap and the overall speeds were lower in other countries, with Switzerland and South Korea coming closest at roughly 1.1Gbps on 5G. Most of these markets don't have millimeter wave access and are relying instead on "mid band" (typically 3.4GHz to 3.8GHz) frequencies to deliver next-gen wireless. In some cases, 5G was so new or channel-limited that the difference was hardly noticeable, such as in Spain and the UK. Australia's 5G was actually slower than LTE, topping out at 792Mbps versus the older format's 950Mbps.
US networks might not want to crow too loudly about their advantage. As we've discovered first-hand, millimeter wave 5G typically offers very limited coverage that falls apart quickly as you venture indoors. That mid band 5G may be slower in theory, but you may hold a 5G connection in more places. And of course, 5G networks are largely empty at this early stage. It could be a different story once 5G adoption picks up and providers become crowded.
Opensignal was optimistic, though. It noted that more 5G services would launch on new spectrum and wider channels, helping deliver on the technology's potential. For now, though, only a handful of people will see 5G at its fastest.