> One doesn't use Kanji anymore, and no one seems to struggle to read it?

Chinese/Japanese has a level of written mutual intelligibility. Korean lost it.

> Japanese on the other hand I have seen even natives struggle to read.

It's like a native English speaker encountering new vocabulary. Happens quite often.

> Heck even the existence of furigana in novels is an admission of this.

I'd agree that manga use of furigana helps (perhaps school-aged readers) reading, but furigana in novels are standard tools in the language that authors can use to achieve some effects that is hard to describe to non-speakers.

Sometimes furigana can be used artistically,sure, but that's the exception to the rule and it's by and large a reading aide in the vast majority of cases, and the inclusion of it in novels aimed at adults indicates that without it the author expects a certain percentage of readers may struggle with how to read the Kanji otherwise.

Why does this tool in the language need to exist? The answer cannot be because Kanji make things easier to read, else you wouldn't need tools to help you read Kanji you at times otherwise wouldn't be able to.

If you come across a word you don't know as either a native speaker of English or Korean, you can at least sound it out, which ups the probability you can connect it with a word you've heard before, otherwise since you know how to type it out it's trivial to look it up in a dictionary. If you come across a word you don't know in Japanese as a native speaker and there's no furigana it's a guessing game. The meaning is slightly more obvious to you, so you might be able to guess, but if you can't guess and you care to know and the word is in print then looking it up becomes a bit more of a pain.

Korean didn't completely lose the mutual intelligibility aspect entirely since the underlying pronunciation of the words still remains and can be used to correctly guess the word in a lot of cases. Like 시간 and 時間 as an example, but there's many, many words I've been able to guess in Korean based off knowing Japanese. I was able to score 50% on TOPIK II reading exam after only having studied Korean for 4 months in large part because of this.

> Why does this tool in the language need to exist? The answer cannot be because Kanji make things easier to read, else you wouldn't need tools to help you read Kanji

This just isn't true. Even most native JP speakers agree that kanji are oppressively hard to learn and remember, so if it were feasible to get by with kana alone, then at least some native speakers would do it in some contexts. But outside of language learning it's virtually never done, and there's a reason for that.

Also, I think you're overlooking that Chinese and Korean have a lot more vowels/tones to work with than Japanese. There are a lot of Chinese-derived compound words that are homophones in Japanese but not elsewhere.

So how are homophones in Japanese understood when expressed verbally?

How much trouble do you actually have with them?

"Science" and "chemistry" are homophones in Japanese: We have special disambiguation reading for "chemistry", bake gaku, used only when misunderstanding is suspected.

There are numerous other examples. Those are all unnatural sounding, mostly industry/field specific, and not replacing the main homophone readings.

1: https://dailyportalz.jp/application/files/thumbnails/width64...

Written kana drops intonation information that's present in speech. Writing with kanji makes up for this, and also allows for more complex sentences that aren't as common in spoken Japanese.

I personally find the most difficult part of reading kana-only text to be detecting word boundaries. It's much easier when kanji is used, and I'm not even a native speaker.

An English analogy isthatyoucouldwritewithoutspacesandbeunderstood but it's more difficult to read and unnatural.

Young gen-z types on Japanese Twitter abbreviate everything, but even they don't drop kanji.

That is what whitespaces are for, which Korean also uses.

Adding whitespace is a pretty simple solution. Heck if you really, really absolutely needed to resolve tonal ambiguity in kana you could add something to Kana to do that. That'd enhance the readability even further since, it's basically impossible for foreigners to learn correct intonation in Japanese unless they explicitly study it and that's on top of memorizing all that Kanji, but it would become explicit. I can recall exactly once in the last 10 years having a conversation where the there was ambiguity between two homonyms and someone asked a clarifying question to resolve it. The vast majority of the time it's just clear from context.

So.. I would say even that ambiguity isn't something people would actually have much a problem with.

> It's the same with homophones in any language,

It really isn't. In conversation fluent JP speakers tend to avoid compounds that would be ambiguous, or add distinguishers like "学校の校歌". Honestly, try converting a paragraph of text from a newspaper to all kana, and having a native speaker read it.

Try have them be educated in a kana only system and then have them try read it. They'd probably do just fine. You'd expect anything you've spend a decade doing to be easier than the thing you've spent much less time doing.

かんちょうが かんちょうで かんちょうに かんちょう された。 Is probably a sentence that definitely requires Kanji to understand the precise meaning given how many homophones かんちょう has, but it's a toy example.

> Try have them be educated in a kana only system and then have them try read it.

I can't, because there are no native speakers who learned that way, as I'm sure you know :D

But there are many learners like that, and my experience in Japan is that anyone who doesn't learn kanji has a very low ceiling on their vocabulary, even if they use the language daily for decades.

Because the reality is that it's hard to memorize 1K kanji, but if you do it then it's relatively easy to learn 10K+ compound words. Without kanji, to reach fluency somebody would have to memorize 5-10 completely unrelated meanings for "kouka", then 5 more for kakou, and so on for every combination of common single-kanji readings.

I mean - if you're in Japan, you surely know people who try to get by without kanji. Do you know any who've reached fluency? Like who could use and understand 5-6 different "kouka"s without any idea of the kanji they use? If your premise here is true then people like that should be the norm, since learning would be so much easier for them compared to those wasting their time on kanji?

So... how do Koreans and Korean learners do it? Not to mention other languages that used to use Kanji but dropped it?

You have to imagine the entire education system and everyone in it got changed to Kana only and Kanji was subsequently removed from modern literature from that point onward. That's the thought experiment. It was even tried successfully in places...

I don't know anything about Korean. It's a different language, and I'd imagine that some of the things I'm saying here don't apply to it, but that's a guess.

For thought experiments, you're assuming your consequent - obviously a society raised without kanji would get by without kanji, though I think the language would have to change somewhat. But for non-hypothetical people that exist now, I think the things you've been saying about kanji not making it easier to read Japanese just aren't true.

Japanese learning materials for Japanese 5 and younger are hiragana only, and I remember finding it annoying.