Exactly. People can understand each other just fine without explaining which word they are using in Kanji. Korea was able to jettison Chinese logograms (Hanja) entirely from its education standards, and the only reason Kanji remains is due to tradition instead of any inherent superiority over the syllabaries.

Actually this is just incorrect.

Spoken Japanese is much more ambiguous. There's a reason subtitles are ubiquitous here. Americans who didn't understand the language tried and failed to get rid of kanji after world war 2. The langauge just does not work without them.

Additionally spoken Japanese uses pitch accent to distinguish homophones such as 雨 and 飴. Long strings of kana are difficult to read period. Native Japanese people struggle and can easily be confused by them in my experience.

Korean isn't comparable because it's phonetically much more diverse and uses spaces.

Kanji / hanzi work just fine for over a billion people. They make skim reading easier and add a lot of character and depth to the language. Westerners have a perception that kanji are hard to learn, and perhaps they're a bit harder than an alphabet, but in the age of computers, it really is a non-issue to learn and use them.

Pitch accent isn't necessary either. Just like English, Japanese has many different regional accents that sound different, yet people from one region can still understand people from another.

The difference is that people write with more homophones than they speak with, just as written English is different from spoken English (more subtle word choice for brevity), but that is not necessary for communication, and written language can adapt just like children's books which don't use Kanji.

Hanja worked fine in Korea, and there still remain a contingent who insist on it, just like there remain people who insist that Kanji is necessary. The fact that people born blind can speak and understand both languages shows this to be a lie.

> without explaining which word they are using in Kanji.

Actually if you spend any length of time in Japan as a speaker, you will notice native speakers writing kanji on their hands to figure out words their interlocutors are using ("wait, you mean this 'kou'? or this one?). If people are not physically present (e.g. phone) you'll hear them describe the radicals (components) of a kanji or ask "is it the 'kou' in 'kousoku' or the one in ...?

Pitch accent + clarification when needed. Subtitles are extremely common here. See my response to a response of this comment for more details.

The tl;dr is that the language is harder in speech than in writing. If you stick to well-worn paths people will know what you're saying, but I often have to discuss the written form of the more obscure words I say or just write it down and show it to my conversational partner.