Why Is Neapolitan the Most Prevalent Pizza in Japan?

Genuinely curious as to why 95% of pizzerias serve Neapolitan pizzas, and where do you get a good Romana? (Not talking about chain stores)

Update for anyone wanting to try a Roman style pizza:

Tokyo:

u/LupusNoxFleuret has suggested this place in Ogikubo – https://maps.app.goo.gl/vjNitLwLc6xbnXQHA

u/enjoyswashlets suggested this place in Yoyogi: https://maps.app.goo.gl/H59GedGHHUkuNBAq6

u/leonmarino suggested this pizzeria in Azabujuban: https://maps.app.goo.gl/CZNJZz5Ve5FqyVBE9

Osaka:

u/No-Bluebird-761 suggested: https://maps.app.goo.gl/7GBK2SbQ6Uuk9pd86

Honorable mention – Sicilian Pizza:

This place in Azabujuban serves Sicilian pepperoni: https://maps.app.goo.gl/HtuvPkK1242hKLv89

My favorite Neapolitanas:

Nakameguro: https://maps.app.goo.gl/VFoUYYouq2bwoMG78

Eifukucho: https://maps.app.goo.gl/tWa4mm4NahjQxi1k7

Kamakura: https://maps.app.goo.gl/ieyiR4CjCCr9NgR7A

Wildcard (honestly the best one I ever had): https://maps.app.goo.gl/8vQo5T6JWhYYhiFg9