The appendix to Nineteen Eighty-Four is written in the past tense, by someone looking back on the regime from a time when it has ended. It is easy to miss, and it is the most hopeful thing in the book.
What it describes is a language engineered to make dissent impossible. Newspeak's purpose, Orwell writes, was not merely to provide a medium of expression for the world-view of Ingsoc, but to make all other modes of thought impossible. The method was subtraction: vocabulary was to be cut down rather than expanded, with every year fewer words and a smaller range of consciousness. Free survived only in the sense of the dog is free from lice. Political and intellectual freedom no longer existed as concepts, because there were no words for them.
The regularization is part of the design. Gradations are removed and replaced with mechanical intensifiers — good, plusgood, doubleplusgood — and the opposite of good is ungood rather than bad, so that the concept of badness has no independent existence. Compression into these forms removes exactly the fine distinctions that proportional moral judgment requires. You cannot say that something was wrong but understandable, or defensible but poorly executed, if the vocabulary offers only good and ungood.
The strong Whorfian claim that Orwell dramatizes — that a thought becomes literally unthinkable without a word for it — is not supported by modern linguistics. People invent words, borrow them, and think in images and structures that language does not exhaust. Speakers of languages without a dedicated term for a concept can still grasp it.
But the weaker version is well supported and is quite sufficient for political purposes. Lera Boroditsky and others have shown that available lexical categories affect the ease and speed of encoding, comparison, memory and communication — that language does not determine thought but does make some thoughts cheaper than others.
And cheapness is the political variable. A thought that requires a paragraph to express, when the opposing thought requires one word, will lose in every setting where time and attention are limited, which is all of them. More importantly, it will lose in coordination: an idea you can state in a word can be shared, adopted and organized around, and an idea you must laboriously construct each time cannot. Unshared thoughts are politically inert.
So vocabulary control does not need to make dissent unthinkable. It only needs to make it expensive, and it does that by removing the words in which the objection is compact.
The observable version of this in real institutions is not a dictionary being rewritten but a vocabulary quietly shrinking around one specific topic. When the plain word for a thing falls out of use in an organization and is replaced by a longer, vaguer construction, that is the process running. The layoffs became a restructuring, then a realignment, then a transformation. The word for what happened to a patient, a customer, or an employee has been replaced by a phrase that has no agent and no injured party.
The countermeasure is to keep using the plain word, which costs almost nothing and is noticed immediately, and to notice which words have become uncomfortable to say out loud.
Cross-ref: doublespeak chapter following