@ Rob Salmond,
Former Reserve Bank Economist Michael Reddell has pointed this out a number of times the main issues (which are amenable to policy)
1) Demand driven by the inward migration targets.
2) Restrictions on land use.
If they restricted the immigration target they would quickly reduce the heat the Auckland property market for starters.
Focusing on ethnicity is always going to lead to calls of racism. Unfortunately if politicians are going to address the housing issue they need to identify the causes. Ex Reserve Bank economist Mike Reddell has pointed out the Auckland housing crisis is the direct result of policy decisions. The liberalisation of immigration from the mid 80's and restrictions on housing supply. The immigration minister could reduce inward migration and take the heat out of the market. Labour should have focused on this as it's a far bigger factor but it would likely have prompted similar complaints. The bottom line should be economic sovereignty and acting in the best interests of NZ citizens regardless of ethnicity.
Former Reserve Bank economist Michael Reddell points out that overseas investment is part of the cause, but inward migration levels and restricted supply are far more significant.