Because much of the infrastructure isn't there or it hasn't been modified to support hydrogen. There will definitely be a hydrogen economy in the future, but that's still in the future.

Renewables need to be funded and built, investments need to be redirected into emerging technologies necessary for the production, transportation and use of hydrogen, e.g., electrolyzers, hydrogen turbines, fuel cells, hydrogen storage, subsidies and policies need to be created to make hydrogen appealing to hard-to-decarbonise industries.

I think everyone understands that a hydrogen economy will have to emerge very soon, but this is a thing with a lot of moving parts, so it's going to take a lot of effort (& money) to make it happen. There are also uses, for which hydrogen will simply not be feasible anytime soon, so other approaches will have to be pursued (e.g. heating and light vehicles).