[modeless]

You're comparing apples to oranges. The 40ms in that video is for Seattle to NY via multiple satellite hops, which is a hypothetical configuration. Elon's tweet is talking about one hop only, from satellite to ground station, which is the intended configuration for v1. There will be dozens or hundreds of ground stations in the US to support this.

For existing GEO satellites, the equivalent measurement is 600ms. That's the relevant comparison. With just 20ms added on top of regular internet latency it would still be usable for competitive gaming at all but the highest levels, as the tweet says.