In the UK, deductibles on mortgage interest payments (known as MIRAS[0]) was abolished for private home owners in 2000. As a renter this kind of always stuck in my craw that homeowners got this preferential treatment and was quite glad it was abolished (even after becoming a "homeowner").
Oddly, buy-to-let landlords do retain this deductible, though HMRC have fiddled around with how this works over recent times[1].
Yes, the BTL sort of makes sense though if you view the mortgage as a business expense, but BTL has had a distorting effect on the UK housing market for too long - changes are desperately needed here, but with so many Tory donors being housing firms, it's unlikely to happen.
Oddly, buy-to-let landlords do retain this deductible, though HMRC have fiddled around with how this works over recent times[1].
[0]: https://en.wikipedia.org/wiki/Mortgage_interest_relief_at_so...
[1]: https://www.gov.uk/government/publications/restricting-finan...