How much more condensed is Japanese & Mandarin text written in books when it comes to reading as opposed to English, where they use multiple letters to spell words and include word spacing?

When I read books in Japanese & Mandarin, it's much more condensed in terms of reading paragraphs or longer blocks of text within a book as they have kanji & hanzi, since they both use a logographic script, but despite both languages being unrelated to each other, they are still mutually readable due to 漢字 however there are false friends to consider. (Eg. 愛人: JP – Mistress / ZH – Lover.)

To put it into perspective something like "Universe" which already consumes 8 letters as each one counts as a "character" so it's longer in that sense, as opposed to 宇宙 only using 2 characters, as each one conveys information: 宇 = Haven & 宙 = Space. It's the same reason why 噂 = Rumor, as a single 漢字 conveys a semantic definition which in return requires multiple letters in English to spell.

Right there you can see the difference as 宇 comprises of ONE CHARACTER while Haven needs 5 LETTERS to spell, same with 宙 as the word Space requires 5 LETTERS just to convey the meaning, as English words consume character count when writing long blocks of text due to each letter being a "character" and include word spacing (thus making it longer).

This is one of the reasons why English text is "wordy" when you are reading paragraphs or longer passages in Western literature (as they consume more space on a book taking up multiple lines just to convey the narrative alone) while Japanese & Mandarin text is more compact since a character has an assigned meaning attached to it due to the languages being ideographic, for example from this text:

ラーメンのルーツは、江戸時代開港に伴い日本に伝わってきた、中国の麵料理であるとされている。そして明治43年には、東京府東京市浅草区に尾崎貫一が日本人向けの中華料理店「来々軒」を開店し、大人気となった。ラーメン評論家の大崎裕史は、この年を「ラーメン元年」と命名している。

拉麵被認為起源於江戶時代 (1603-1868) 隨著日本開埠而傳入日本的中國麵條。1908 年，尾崎寬一在東京的淺草町 開了一家中餐館「來來記」，深受日本顧客的歡迎。拉麵評論家大崎弘將這一年命名為「拉麵元年」。

Ramen is believed to have its roots from a Chinese noodle dish that was introduced to Japan during the Edo period (1603-1868) with the opening of Japanese ports. In 1908, Kanichi Ozaki opened a Chinese restaurant “Rairaiken” in Asakusa-ward, Tokyo, which became very popular with Japanese customers. Ramen critic Hiroshi Osaki named this year “the first year of ramen”.

I find it easier to digest information in Japanese or Mandarin for this reason, when it comes to reading books. When reading books in English, it's tiring to read long blocks of text or paragraphs as they use multiple letters to spell a single word along with word spacing (consuming more of the page). Depending on the author and their writing style, some paragraphs are a headache to read in English.

Due to both languages having 漢字: information is much more compact, as words are conveyed semantically, for example 龍 consists of a single character in text while dragon uses 6 letters to spell and longer in word length, this is why English words are cumbersome to read (as they need to be at a set font size) while in 日本語 or 中文 you can srhink the font size and the text is still legible to read.

When you read books like GoT in Japanese or Mandarin, it's much more compact due to the huge presence of kanji & hanzi already conveying concepts, but in terms of Japanese: you have kunyomi, onyomi and nanori readings of Kanji while in Mandarin you have tones (in spoken dialog) but in written text, you need to know which is the correct way to read that word.

In terms of English, people say "you can still read it despite not knowing that word" but that does not mean you know the definition right away from the top of your head if you've never heard of that word before despite using an alphabet, it does not convey semantic meaning by a single letter, if I write 躊躇逡巡, it only uses 4 漢字 while hesitation and vacillation requires 26 letters and 2 word spaces.