This, delivered on 6 February 1940, was fortunately recorded for posterity and can be listened to on the ngataonga.org.nz website here.
At the 5:52 minute point he says: “Clause 1 of the Treaty handed over the mana and the sovereignty of New Zealand to Queen Victoria and her descendants for ever. That is the outstanding fact today. That but for the shield of the sovereignty handed over to Her Majesty and her descendants I doubt that there would be a free Maori race in New Zealand today.”
This is indeed fundamental — The British Crown was given complete sovereignty, where Maori would have equal rights as British citizens, but not special rights: there was no co-governance agreement as the Jacinda government now intends to institute in reference to its version of the Treaty. Note also that Apirana Ngata refers to New Zealand as the name of the country, and not the much-later-coined ‘Aotearoa’.
That doesn’t mean everything had been wonderful in the preceding 100 years and the grievances and unhappiness get mentioned too. Addressing these has been a slow process over the last 50 years or so and still continues.