No its the equivalent of capital gains tax that is no longer levied after 5 years of ownership. The truth is, there is no property purchase tax, it is property transfer tax, 4% paid half by buyer and half by seller.
In the lively years of property sales the seller would insist he was not paying (often by saying the price includes a reduction to cover his 50% share of the tax liability). In recent times buyers know they have the upper hand and are sometimes insisting that the seller accepts his tax responsibility.
On top of that, tapu values are no longer piddly little amounts, they are close to real market value - making the property tax a far more significant amount - another reason why buyers don't want to pay it all, and they know the law agrees with them.