To be precise, newspeak does function by a direct reduction of vocabulary. Instead, newspeak works by expanding the number of meanings a single word can have, so that every sentence can be interpreted as supportive of the party, and the ‘grammatically correct’ meaning of the sentence is the supportive interpretation.
The closest approximation of newspeak in English is the sentence “That didn’t work, did it?” If you respond “Yes,” that can be interpreted as “Yes, you are correct, that didn’t work.” And if you reply “No,” that can’t be interpreted as “No, that didn’t work.”