This is a restaurant, not housing

Not being able to communicate, participate, doesn't help either side. Buying a house, without being able to communicate is on its way to forming and insular community and not simply being denied service that is otherwise open to the public.

I'm not an expert on Japanese culture, but I don't think they have the "melting pot" cultural identity that America has had historically.

Do you believe that anyone existing in America must speak English

Yeah, eventually. If I'm going to live in a country indefinitely, I'm going to try to learn their language. If I'm in France for more than a year, I'm going to try to learn French. I'd expect the same of friends and family. It's not racist to expect people living in a place long term to be able to converse with the locals.

If they're working here for just a summer or two and spending most of the year in another country, no.

and only English?

No?

America is a country founded upon immigration, so it's not a comparable example. In broad terms, Japan is historically a fairly homogenous nation ethnically, culturally, and linguistically (and yes, I know those are very broad terms, I'm talking relative to North American countries like the US and Canada).

If the 1600s-1700s had gone differently, and North America remained predominantly populated by Native peoples speaking Native languages, then yeah I'd say it's totally within their rights to expect visitors to either learn the local language and attempt to integrate, or be left out of certain parts of society such as restaurants that want to cater exclusively to people who speak Algonquin or whatever.

Show up in Algiers and try saying "Sorry, I don't speak Arabic. Do you have a French menu?"

It's not their fault which Lemmy server they were born into

Yeah, team sports!

/s