E.g. 海, 洲, 流 (sea, continent, flow) all have three dots on the left indicating they relate to water.
And 领, 玲, 铃 are all pronounced ling due to the 令 component.
Characters that aren't widely used you don't need to learn to write, and reading is much easier than writing. If you see a big complicated character in a noodle-y context you pretty much know it's going to be biang.
If you don't know the pronunciation of a character it's not too far from not knowing the meaning of a random English word like "kaiserin", apart from being slightly harder to guess pronunciation on average.
You are correct, though: This is not failsafe and characters can have multiple readings or lack this phono-semantic notion altogether (also, since the characters are originally Chinese it doesn't work as well in Japanese, I believe), but I think it is the closest thing to guessing a word's pronunciation that these languages offer.
[1] https://en.wikipedia.org/wiki/Chinese_character_classificati...
Take your example of 仲. How is that pronounced? In Japanese, 人 is typically pronounced "jin", "nin", or "hito" depending on context. 中 is usually pronounced "chuu" or "naka." How do I know these things? Rote memorization. While I can recognize that 仲 contains 人 and 中, that doesn't tell me how to say 仲. The only reason I know its pronunciation is because I memorized it. (In this case, it happens to be the same as 中.)
And that's just for reading. Writing is worse. Character amnesia is extremely common among native speakers of Chinese and Japanese. From Wikipedia[1]:
> Another anecdotal example can be seen during a spelling bee show hosted on CCTV in 2013, where only 30% of participants were able to write "toad" (Chinese: 癞蛤蟆; pinyin: Lài há ma) in Chinese.
That sort of thing simply can't happen in phonetic writing systems.
That's the thing I don't get. You may be able to guess the words, but would the characters allow you to pronounce it? In English, and most other languages, you can spell your way through pronouncing a word, even without knowing it's meaning. Is that possible in Chinese or Japanese?
It also seems like you would need to be constantly updating computers to allow them of deal with new characters.
The argument that "these characters aren't widely used" isn't really helpful. The characters either exists or they don't. Because you might need it in the future means that you need to deal with it's existence. X isn't a widely used letter in many language, so should we just throw it aside? In case of the biang it might be more akin to throwing out a word, because it's rarely used, but still.