The net effect of these rule changes is that more flights will be canceled for weather or ATC reasons and customers will have no recourse other than to wait until the airline has its next seat available. These changes are not good from a macro level though for the ~12000 passengers/year who were previously on tarmac delays of > 3 hours it would be nice. It is a classic game of making people so enraged by an outlier statistic that they're willing to forgo real protections for the sake of being "protected" against something that is almost never going to happen to them.