We want higher taxes on the rich, the other rich though
State and local tax deduction is mostly used by the wealthy and is unfair to residents of lower-tax states. The rich living in high tax states are crying because they have to pay more as they can't deduct more than $10,000 in state taxes. So like always, those who want higher taxes complain that they meant other rich guys.
As I've pointed out if you make more than $40,000 you are rich by world standards. A fact not lost on people that want to collect taxes and raise them.