This is an argument that will continue until we have a comprehensive capital gains tax (no exclusions even for your own home).
Prior to 1987 everyone was investing long term in the sharemarket, post Oct 1987 a lot of investors actually realised they were traders and their losses were deductible. There were some tax cases but I don't remember their names. Prior to the GFC people were buying coastal sections to build a holiday home (or two) post GFC they were speculating on land. Bond investors became bond traders after the finance company debacle although the rules were pretty specific I do recall hearing about an old dog on this site slipping some debenture losses through his income tax return.
Time to stop the bull**** and putting normally honest NZ citizens in a situation were they feel compelled to lie for personal gain. After the next big slump in asset values the govt of the day should bring in a capital gains tax.