> JP's phonetics, for example, are dead simple compared to English's

I'm not so sure about that. Do you know about pitch accent?

https://en.wikipedia.org/wiki/Japanese_pitch_accent

I'm not a native English speaker, so I don't really know why, or if, there's a problem for native English speakers to learn or "get" pitch accent. For speakers of many other European languages Japanese pitch accent is not tricky. You listen, and then you speak. Just as you would listen to English, and repeat it the same way.

Japanese, despite being extremely logical and so beautiful in so many ways, is still hard to learn for me, and of course learning the writing system is not done in the blink of an eye (unlike the Latin-based writing system we use), but pitch accent isn't really the problem here.

Is that any more complicated than English stress, though? And regardless, Japanese has a very small number of phonemes (compared to English) and extremely restricted phonotactics.

Yeah, but I don't expect this to be substantively harder than learning most regional accents (could be wrong), and afaik it's also not critical for legibility.

It's not unclear at all without the apostrophe, because in German, compound words are written without spaces. If it was indeed a bar that specialized in a drink called "Rosis", it would be spelled "Rosisbar". The space makes it immediately apparent that it's a bar operated by someone called Rosi.

Compare:

- Sport Bar

- Lounge Bar

- Cafe Bar

(All from real german bar names.)

- Rosis Bar

Rosis could just as well be a word like Sport, Lounge or Cafe.

Correct German orthography would require a hyphen for the interpretation as a compound noun.

Rosis-Bar = a bar serving (or otherwise related to) “Rosis”

Rosis Bar = Rosi’s bar

Do you usually use GPT4 to translate from English, or was that just for the example in your comment? Because the translated output highlights the major problem of this learning-through-AI approach: The generated output can just simply be wrong, like it is here (both the Japanese and German).

I think it is good enough to "break into" the text. It's not the most literary translation but you could just start from a Japanese text if that's what you wanted. I went for modding the English text I am currently reading as a language exercise.

The concern is the reader has zero idea the translation they're reading is wrong

As long as learners are aware, I agree. Getting you to the point where you can start reading "regular" texts in a language is worth it even if some of what you think you know at the point you get there is wrong.