The US saw similar efforts in Detroit and other Rust Belt cities. That mostly just resulted in asset flippers hoarding houses and letting them fall into further disrepair. I wonder what steps Japan is taking to mitigate that possibility.
Japan is a peculiar country, I'd bet a few dollars that they won't abuse the system that much.
Houses depreciate quickly and I don't know that land appreciates at a very high rate, so there isn't much to abuse in the first place. And because japan's zoning is not completely stupid, redevelopment can be done piecemeal. So if you buy to flip, either you flip very quickly for little to no gain or you don't and the neighbourhood gets redeveloped around and without caring about your property, which will likely be too small for anyone to be much bothered. The exceptions could likely be significant plot of lands like old temple grounds and the like which could sustain an entire development on its own.