Deductions for all three of those things (mortgage, charity, state sales taxes) help EVERYONE who pays taxes. If, OTOH, what you are saying is those deductions don't help lower income people because those people don't pay taxes anyway, then that argument is a non-starter with me.
A LOT of charitable contributions will dry up if there is no deduction for them. Rental prices will go up if the owners have to pass the cost of losing the mortgage deduction along to the renter. These things have consequences.