The error message could be better here, there are no videos to download as forecasting is not the benchmark name. Instead, the CLI does not split up the forecasting or hands benchmarks, it is all considered “fho” (see: FHO Overview | Ego4D to understand). Forecasting and Hands-related benchmarks are all derived from FHO.
i.e. use --benchmarks fho. Using your example, please run: