It’s more a comparison of their actions and behaviors and not necessarily them as people.
The average orc in Orgrimmar is not bright green with glowing red eyes drinking the blood of its enemies. Calia seems to think that the Forsaken are the exact same they are in death as they were in life. The only time we’ve seen undead as depressed humans and not the emotionally stunted people who want to leave their mark on a world that forsook them was in before the storm. So you have a leader that isn’t even really undead compared to the Forsaken, feels zero of the downsides of undeath, thinks that the Forsaken can be made better by giving them hugs and kisses now taking over their leadership. To call it grating is an understatement. Water and oil.
Edit: it would be like the blood elf Druid in the botica or however that dungeon was spelled showing up to take over the Druids if malf went away.