At the very least we know Jaime doesn't have a moral problem with killing a large amount of people, since he still supported Cersei after she blew up the sept.

And my other point was about how one person can be worse than the other even if the other has a higher body count. Like, I'm sure Tormund or Sandor's body count is higher than the High Sparrow's, but the High Sparrow is definitely more awful.