The population of Japan has been in decline for a long time. It's no secret. I've seen news reports of towns being abandoned simply because nobody is living there. I've seen predictions that around 2050 Japan will have a population about equal to what it was in 1908. What does this mean for the Japanese language? Japan may have to allow more immigration and do more teaching of the language to immigrants to slow down the decline. I don't believe that Japanese will disappear or become extinct any time soon, but watching the Japanese situation may give other threatened or disappearing cultures some ideas about how to hang on to existance.

I don't think the number of Japanese people will ever be so low that the language/culture can get extinct.

[uninformed opinion]And I don't think the Japanese government is keen on a lot of immigration. They have been in isolation for centuries, and even now, they don't really like foreigners.[/uninformed opinion]

Yeah, Japan is still very populated (look at the size of Tokyo?) so it shouldn't be a problem for a long time and I highly doubt it'll become extinct. I just worry that English will take over every language in the world and I don't want that to happen.

They love them if they're white.

Pretty much true.

But oddly, not if they're Asian, or at least Korean...

Koreans have it alright. But you're right about other Asians, especially Southeast Asians.
This is a truly unfortunate issue in Japan. But I think they're getting better about it.

What other "threatened or disappearing cultures" are in a situation remotely like that of the Japanese? Japan still has over 127 million people. Latvia's growth rate is also negative and there are barely two million of them. If you count only ethnic Latvians, there were more around in 1935 than there are today. But at least they still have their own country, which is more than you can say for the vast majority of ethnic groups in the world.

Joe Biden recently remarked that Russia has a declining population base. I suppose the Russian situation is most like that of the Japanese. Admittedly, the reasons for the Russian decline are quite different and more pathological. Russia would benefit from less alcoholism and Japan from less workoholism.

Maybe if Japanese language gets to lose speakers due to the decline of native speaking population, maybe they should just get rid of Kanji and write everything in Hiragana and Katakana.
That would save me a good deal of effort earning it!