So much this. Was going to reply that Daenerys had already given her reason for why she thought the people of KL were not innocent, but Svalbard bet me too it.Dany says that the people of Slavers Bay rose up in support of her and she holds the people of Kings Landing culpable by not doing the same.
In the books Danny's legacy in Slavers Bay is one of slaughter.
To play devils advocate though... There is a problem with this. They surrendered and rung the bells. That was the people's decision, not Cersei's. So they did rise up against Cersei, yet Daenerys killed them anyway. So she was ignoring her feelings about Slavers Bay as well.