https://www.railwaygazette.com/projects-and-planning/first-lightline-tram-arrives/59231.article
Construction of this LRT caused controversy among bus companies and residents using private vehicles. The former ones say "It will reduce passengers boarding our buses."
The latter people say "traffic lanes will be reduced to get land for LRT trucks. It will cause traffic jam."
Since many public transportations are operated by private companies, construction of new transportation system can easily irritate private bus companies running parallel with it. Furthermore, many residents think construction of it must be inefficient use of tax.
So, it's difficult for Japan to build new transportation systems easily.