Sure, though 20 ms getting you to a fat node is pretty good, especially if you're in an underserved area. The net time cost is actually the difference between this and straight-line overland distance, which is both not in vacuum and hits node latency.

10 ms is roughly datacenter lag (or was a few years back). 100ms is good cross-country pings, 300-600 is continent-to-continent links.

Figure on edge caching aas well.