Perspective from an accountant
After reviewing personal tax returns every year I'm reminded that there are a ton of "mom and pop" investors that own 20+ investment properties.
They were able to effectively purchase a scarce income producing asset then utilize leverage to keep buying more and more properties during a period of high inflation and growing population to break the system.
These people should be the lowest hanging fruit in efforts to lobby the goverment. The foreign buyers ban, under used housing tax etc. all sounded good on paper but were a nightmare to implement and full of loopholes.
However lobbying for progressive tax burden on individuals (including related corporations, partnership etc.) that own more than one single family home seems like an incredibly simple solution with little to no downsides.