Look at the all blacks. No one says that they poach Tongans, Samoans, cook islanders etc because they are classified as kiwis with other heritage and Nz develop them and make a name out of them. Not the other way around
All Blacks are CONSTANTLY having to dispel the myth that anyone that’s brown with a non-Maori surname is a “poach” particularly from those that don’t know the ethnic make up of NZ.
There’s a perception that we go on scouting missions to the islands to steal already developed players...
I get what you mean with the heritage thing, I think most people can lay claim to being eligible for a country other than what they identify themselves as. I feel the major difference is many pasifika people are only a generation or 2 removed so parent and grandparents have a stronger life influence in cultural identity.
I identify and practice with some of my Father and his parents (1st gen NZers from Europe) culture but I could never bring myself to play against NZ