Owning an investment property is for the purpose of maximising profit, therefore there is no incentive for landlords to replace inefficient costly appliances with efficient ones, or for MPs who are landlords to bring in legislation requiring that. Tenants pay for their landlord's greed. MPs won't make changes against their own financial interest, so nothing will change till MPs are not personally benefiting.
I like where you're coming from, I really do, but I don't think this is the solution. I say this as a renter myself. MPs being landlords a symptom of the fact they're older, and that we have a system that incentives housing as an investment (eg. negative gearing, no ownership caps, etc.). MPs are mean't to be representative of the community, and unfortunately owning housing only as an investment is them being representative of the community. We really just need to massively increase supply.
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