Well, that answers that. Adora has a connection to the She-ra's of the past, but not to their actions.

She's got no grounds to act like anything they did is her responsibility.

"Does it matter what they think of Mara?" It's an important question. If making the First Ones - if making Adora's parents - understand is something that Adora needs to do, then Catra will put everything she has into making it happen. "...You're different people, Adora. You know that, don't you? Whatever issue they have, that's with Mara. It isn't with you."