Tesla has been known for a long time to game EPA numbers. Here's an article from 2020 talking about it: https://insideevs.com/news/407807/eletric-car-real-world-range-tested/

It's not a best case scenario - it's a precisely repeated series of accelerations, cruising with a specific amount of resistance applied to the wheels, and braking.

It won't match any real world drive. In the real world there are other variables, traffic, wind, hills, speed limits, etc. It's also intended to be a fairly typical highway drive, so in ideal conditions you will do better than the EPA range. Down hill, for example, the cybertruck can drive forever (unlike an ICE, which is so inefficient it uses energy even going down hill).

I've found EPA MPG estimates to be fairly accurate. Unless I'm driving aggressively or there's a lot of elevation change the highway average has been spot on the EPA number in every car I've driven enough to pay attention to the MPG.

Because a lot of other EVs that he's run on the same test exceed the EPA numbers, some by a quite considerable margin. The Taycan for example is well-known for exceeding the EPA estimates by as much as 50%. He recently tested the EV9 (a brick) on the same test in similar temperatures, and it also exceeded the EPA numbers.