I don’t know if you’ve tried to scrape or programmatically download a lot of websites recently! It’s not possible to repeat their data collection process anymore.
Japan isn’t a federal government, so the decision can happen at the national level because prefectural and local governments zoning ability came from the national government.
I don’t think the federal government could de facto change this, though in practice they have levers available.
I agree with the general sentiment that the structure of society is going to change, but I don't know what the satisfying solution is. It's hard to imagine not participating will work, or even be financially viable for me, for long.
There is a CORS preflight check for POST requests that don't use form-encoding. It would be somewhat surprising if these weren't using JSON (though it wouldn't be that surprising if they were parsing submitted JSON instead of actually checking the MIME-type which would probably be bad anwyay)
I don’t think you have to go from here to planned economy straight away. There are capital gains taxes between the current level and 100% which might produce better outcomes.