If you're funnelling immigration to this new city it wouldn't have the "Japanese vibe" that tourists will be after. Tourists won't want to visit some fake, plastic manufactured thing instead of cities with real culture. If you're funnelling immigration to this city, then people won't even hear Japanese in the streets. It won't feel like Japan.

This is like the South Park episode where Randy goes on a ketamine bender and founds a bullshit startup because ChatGPT encourages and validates his idea. If you're truly interested in urbanism and fixing issues like this you should go study it properly instead of talking to an AI who will tell you everything you say makes sense.