Hawke probably killed more people over the course of one act than literally anything Anders could have done with the Chantry, tbh.
Meredith probably killed more people on her way to the Gallows to annul it than Anders did with the Chantry, tbh.
Hawke over the course of the whole game has definitely killed more people than Anders did with the Chantry.
Over all three acts, you get a higher kill count in the Chantry, than he does with the Chantry.
…. Nope, still think he was right.
Like, sorry– not sorry. After nearly a decade of trying to peacefully bring change and watching his people die or be made tranquil, he made a statement with it as a last resort. The couple dozen people lost in the Chantry will never equal all the people he was trying to save and couldn’t because of the Chantry as an institution.