I don't know if anyone phrased it similarly before Brave New World, this is the earliest I can think of -- mass production results in drops of quality.

I studied art, specifically, book illustration. For my graduation project I printed a book: Moscow-Petushki by Venedict Yerofeyev. Well... not really. It was a year-long project during which I made a few pages for select chapters from the book in a combination of mezzotint for the illustrations and woodcut for the text pages. The woodcut part came as a belated realization that I won't be able to pull out the text in mezzotint, but I didn't have enough time to redo the illustration in woodcut... so, I kind of botched it.

I also made the book cover, which was kind of a canvas pulled over a wooden shape and then glued together and varnished... in the end, it was kind of disappointing. Well, anyways, I was done with it, it was over... and I ever only printed one copy, and I lost it few years after the project was over.

The moral of the story though: the time and effort it takes to make one book like the Encyclopedia in OP is enormous... it could take generations of artists to do something like that (well, in this case, it was probably many artists working together at the same time to produce different pages). A project of making such a book today would've been extremely hard to pull out financially -- just imagine paying a dozen of artists for a few years to get like maybe a hundred of copies, if you are lucky.

But... if you are willing to compromise, you can still find some decently made books. The knowledge of the craft hasn't completely disappear, however, it's becoming more scarce...

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Here's another personal anecdote: at one point in my student life I was hired by the state's hotel for official guests to "decorate" the guest book. Well, you see, the hotel kept the guest book in which they requested that guests write something about the hotel. So, they had autographs of all sorts of presidents, prime ministers, movie starts etc. What they asked me to do was to write their names in some hand-written font.

The last person who did that either died or moved to another city / country about ten years before they found me. They kept advertising the job in the art academy I studied, but nobody took it because calligraphy wasn't really well-taught there (it was my second time getting an art degree...) So, I happened to know how to do it, and got a decent gig job for two months. But, apparently, it was so rare that they waited for ten years just to get one person to apply.

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Another interesting aspect of (more) modern book publishing was in the 90s when both the pagination technology and printing technology changed rapidly due to computerization. This created a lot of opportunity for people with some computer skills, who didn't know the trade of printing well to produce absolute horror-show of books. It was so bad that people in academia first really wanted to prohibit the students from using computers for making books :)

We still live with quite a few relics from that era though. For instance, the atrocity that MS Word is... it's the typography made by people who don't know what typography is and yet are somehow put in charge of making the nightmare choices that they've made...

But, in general, the atrocious text formatting everywhere on the Web... I guess, it just became so habitual, we mostly forgot what good typography looks like.