Mortgage interest is not tax-deductible in Canada.

Mortgage interest for commercial entities is tax deductible in Canada, just like any other business loan. It's only personal residential mortgages that are not deductible in Canada.

It seems to me that this difference favors landlords over owner-occupants when it comes to buying property [which does not seem to be beneficial public policy]. With interest rates as low as they are, this is maybe only a medium-sized problem, but when interest rates rise again, this is likely going to exacerbate the difficulty of people beginning their home ownership "ladder" because landlords can literally outbid them by the difference in tax policy.

That's very different than what the OP was talking about, no?

Which OP? Many upthread are talking about mortgages a subset of which would be deductible in Canada.