The vast majority of mortgages out there today are fixed rate, not adjustable rate. That means that the interest homeowners are paying is locked in regardless of the rates in the market today.
Most homeowners still have a substantial amount of leverage though, and you can refinance every X years. On top of that, rising rates reduce house values.
Most of my parents' net worth is in either residential or investment real estate, and low rates are very much good for them.
