I loved the book. However, I can certainly understand that it is difficult.
Not only does it use difficult words, but it is full of cultural difficulties. It also includes satire and irony, and a somewhat experimental writing style, not straightforward storytelling.
As a matter of fact, as a US native speaker, there are things in the book I didn't understand right away, culturally, and I am sure there are things I don't understand yet.
Huxley describes his dystopian world from within, and, unlike other similar novels, he does not explain many of his references. In George Orwell's Nineteen Eighty-Four, Orwell tells us what a "telescreen" is, what Newspeak is, and so on. For example, Huxley never tells us what a "Malthusian belt" is. We are supposed to know who Malthus was. We are supposed to guess that "Malthusian" means "limiting population growth through the use of contraception." And we are supposed to guess that a "Malthusian belt" must be something that women carry contraceptives in.
The book is very much of its time, 1931. A detail I didn't understand when I read the book the first time was the degree to which Henry Ford was once admired and lionized. That was a phenomenon of the early 1920s. Huxley satirizes the "worship" of Ford by making Fordism an actual religion. Ford's reputation has faded for many reasons. We no longer think of him that way, so the satire falls flat.
Huxley does not care about making things easy for a reader. Huxley wrote another book in 1936 entitled Eyeless in Gaza, in which, rather than tell the story sequentially, he scrambled up the chapters and presented them in a random order.
I wonder how many foreign-speakers can identify
"'Civilization is Sterilization," I used to say to them'" as a satiric reference to "Cleanliness is next to godliness?"
I wonder how many can recognize
Streptocock-Gee to Banbury-T,
To see a fine bathroom and W.C.
as a parody of the nursery rhyme
Ride-a-cock horse to Banbury Cross
To see a fine lady upon a white horse?
I wonder how many native speakers understand what Huxley was getting at? I don't, myself, not completely! When I first read the book, as a US native, I didn't know what a "W.C." was. (It stands for "water closet" and means the fixture I call a "toilet.") "Banbury T" is a transformation of "Banbury Cross," with the cross transformed into the T of "Fordism."
But what is "Streptocock-Gee?" Probably the one of the families of the infectious bacterium Streptococcus, which are classified into groups A, B, C, and G. But why does he bring in streptococcus here?
In short... by all means, read this book, but don't be surprised or bothered if there are many things in it that are hard to understand.