Not 100%, all surviving Moriori are a mixture of Maori and Moriori. At this point probably some European as well.
The “full blooded X” argument is an attempt to disenfranchise Māori from their whakapapa. If a person can and wants to trace their lineage (whakapapa) to any iwi or waka then they are Māori.
I don’t know, I have a not insignificant amount of indigenous blood (not Maori) and without any cultural ties I don’t think it’s significant as an individual. My family was raised and then raised me with no real connections to any of our hereditary cultures.
I don’t really have an interest in submerging into a culture that is foreign to me, nor am I interested in attempting to benefit from any sort of reparations. I’m just a white girl with a large fraction of indigenous blood.