That's according to linguist Dr Julie Barbour who says English is already the dominant language in Aotearoa New Zealand, so making it an official language does little more than reinforce that dominance.

The English Language Bill - which is just two pages long - states English "has long been a de facto official language in New Zealand, that is, widely used and accepted as an official language, but its official language status is not set out in legislation".

The bill is part of the coalition agreement, brought forward by New Zealand First and passed its third and final reading at Parliament late July.

Speaking at the third reading, MP Casey Costello said the bill was important to the "hard-working Kiwi battlers" her party represented, and denied it was a waste of time. She said the bill provided clarity and certainty in legislation, and changed none of the existing legal protections afforded to te reo Māori or New Zealand Sign Language (NZSL).

The bill drew the ire of the opposition, with Green MP Tamatha Paul calling the bill's proponents a "bunch of snowflakes that hear the word Aotearoa and cry themselves to sleep", and noted English was not an official language of England.

Her speech has generated millions of views online, making headlines across the world. Paul called English a "bastard language" and criticised the legislation as unnecessary.

While the wording may have been provocative, Dr Julie Barbour a senior lecturer of linguistics at the University of Waikato and secretary of the Linguistic Society of New Zealand, said there is truth behind the broader argument that English is a language shaped by contact, conquest and the languages it encountered.

"The description of English as a predator language is quite a useful one because it's been carried with military powers often behind it," she told RNZ.

"The language has come into new locations where there are existing languages, often many. In the case of Aotearoa, there was a single indigenous language already here when English was brought in.

"And what has happened is that the language has kind of swallowed the indigenous languages of the different contexts where it's been taken to. And in many cases, those indigenous languages have been really actively suppressed by the colonial powers."

Barbour said English itself was not a "particularly old and ancient language".

"It's only been around for about 1500 years and it developed out of dialects of Germanic languages that were carried by the Germanic peoples from Western Europe when they travelled over to England. So they actually arrived in England after the Romans left. And so there's kind of a perception that English is a daughter language of Latin, but that's not actually the case. English is a Germanic language."

She said English absorbed vocabulary from the languages and cultures it encountered.

"The core of the English language is Germanic. And a lot of our simple vocabulary is Germanic in its origin, but a lot of the vocabulary that we have has been either acquired because English was ruled, governed by other countries, France in particular, or it's vocabulary that English has absorbed as it's come into contact with entire cultures," she said.

"That vocabulary is not Germanic in origin. It originates from a whole lot of other languages that English speakers have come into contact with."

Barbour said the history of English in Aotearoa is significant because early settlers relied on Māori language and knowledge to survive in an unfamiliar environment. Māori names for plants, birds, fish and places were adopted by English speakers, but the same willingness to learn te reo Māori did not last.

"What didn't happen, what didn't stick, was the knowledge of te reo Māori that the earliest settlers had," she said.

"The very earliest settlers, we know from written records that they learned Māori. They needed Māori in those really early years of contact.

"But after Te Tiriti was signed, that all flipped and the discourse flipped. And that's where you get a swing towards English."

Barbour said the English Language Bill needed to be understood within that wider history. She questioned what the legislation achieved when English already dominated almost every major institution in the country.

"It changes absolutely nothing about the way English is already being practised as the dominant language of all of our major institutions... It changes nothing. It's literally five lines of something which already is true. It's a bizarre piece of legislation.

"I find it utterly bizarre, and it's just another expression of that monolingualism."

Barbour said the legislation risked reinforcing the idea that English needed to be protected, despite te reo Māori and NZSL requiring considerably more support.

"It's problematic because it's so unnecessary, and it makes people think that it is necessary," she said, referencing Te Ture mō Te Reo Māori the Māori Language Act which recognised te reo Māori as an official language and taonga (cultural treasure).

She also said that multilingulism was a "normal situation for human beings", and that we should be encouraging it.

"The world is not naturally monolingual. The world is multilingual," she said

"Monolingualism comes with that push for ultimate power and control. It's a form of control... I speak the language, I have the power.

"When you learn a new language, with the people who speak that language, whose indigenous language it is, you have access to a different way of thinking about the world," she said.

"And that different way of thinking about the world is so important in a world where we haven't gotten things right."

RNZ has approached NZ First leader Winston Peters for comment.