I think that the attitude of the government has shifted but not by _that_ much, and I don't think we can discount the past 50 years of urbanism as having no effects (plenty of the stores I'm thinking about aren't 100 years old after all). But I won't pretend to believe that we can't have nice things taken away from us.
I don't know how we get new Nakano Broadways in the current environment.
> I am worried that the Tokyo government isn't particularly interested in preserving these places though
You're basically agreeing with me. The fact that Tokyo has interesting places now doesn't mean it will in the future.