One of my Hawkes sided with the Templars and spared Anders in order to get his rivaled butt in on the crackdown and try to delegitimize his stance as radical mage revolutionary. Rather than 'Anders, the revolutionary martyr against Templar oppression,' it was 'Anders, the insane abomination who killed innocents to provoke a mage massacre he participated in.'
If Anders is going to be remembered by history, it will probably be as one of the more hated figures of history. The cautionary tale of the seemingly nice revolutionary maleficar that both mages and mundanes would use to scare small children. Maybe even become the Thedas setting's equivalent to Godwin's Law: 'as an argument continues, the probability of Anders being brought up approaches 1.'
Whether the mage rebellion succedes or fails by any meaningful measure, Anders may well be a stigma mages will have to work against for millenia. Think of how much effort and burdens of disproof will be needed to distinguish any talk of mage freedom and justice from, well, the guy who was literally a walking composite of mage freedom and justice.