A quick Google search of “Mexican Restaurants in Tokyo” brought up over 30 results in Tokyo. Hell, the other day I was watching the original Iron Chef from the 90s, and they brought in a Japanese Mexican Chef as a challenger.
There’s over 30 mexican restaurants in my town of less than 30,000 people.
Tokyo is LITERALLY the biggest city in the entire world. 30ish restaurants is absolutely a needle in a haystack.
I calculated an estimation for the amount of the workforce in mexican food
(Mexican restaurants) * (avg workers per restaurant) / (population) = percentage of workforce
30 * 15,28 / 30 000 * 100 = 1,53%
It is probably a higher percentage because this doesn’t factor in the unemployed and you said it was less than 30 000