Good points but I'll play devil's advocate.
With the housing bubble effectively deflated any suggestion to eliminate mortgage interest deductibility becomes mute as a remedy to cure the problem. Deductions based on tax bracket percentages is a losing proposition in terms of absolute cash flow. What benefit is realized through partial reimbursement of debt service expense on an asset class with a declining value trajectory? Leverage opportunity is non-existent.
Additional disincentives to purchase real estate will only serve to further depress home values in the short term which affect every home owner and the economy as a whole. I agree the elimination of interest deductions except for mortgages singly benefited those qualified to purchase a house, which after 1998 wasn't strictly defined as a wealthy class. Years ago home ownership was determined to be in the national economic interest until Fannie, Freddie and Franklin Raines gamed the system and perverted the concept via powerful lobbyists with huge personal and political agendas. This article
provides some statistical background of their excesses.
Before the bust most of those who couldn't afford to purchase a home and "reap" the benefit of mortgage interest deductions were net tax recipients under the tax code. I see no reason to provide even greater disequalibrium in income redistribution before a thorough cleansing of the entire system.