#raydia

For starters, they both share trauma; their parents abandoned them. But, their reactions to the trauma were complete opposites:

Rayla -> She abandons the people she loves before they can do it (Even if she doesn't do it consciously, e.g. Her leaving at the end of TTM)

Claudia -> She sticks to the people she loves and doesn't let them go even when it could be for the better. E.g. Bringing back Viren. (Tho for a moment she left Terry, she came back eventually)

They share that trauma and can bond through it because they can understand each other at a level no other character can.

Yes, Callum and Ezran also lost their parents and they used to be friends with Claudia. Yes, Soren also lost his parents. Yes, Terry is there for her, he loves her and she loves him.

So why can't any of them help her see things clearly?

Soren -> Because he's the one of the people who abandoned her in the first place. He's one of the causes of her trauma. He also has tried to reach her but couldn't do it (First in S3 when he asks her to go with him and Claudia refuses and then in S4).

Terry -> Same as Soren, he may have not abandoned her (yet, I have the theory he'll join the dragang in S7 because he thinks is the only way to save Claudia atp), but at the end of S6 he tried to make her chose a different path and it didn't go well, she still chose to free Aaravos.

Ezran -> They've had a heart-heart talk before in S2, and then Claudia fought against him (and Callum and Rayla) in S5. Ezran may be able to give her another chance if she explains herself and wants to be redeemed. He also lost his parents, but as he thinks in the novelization of book 2, not because they chose to leave, they were killed, there's a world of difference.

Callum -> Same with Ezran, he also lost all his parents, but it's still different, and this is the more clear representation of what it is to lose a parent because of an outside cause like murder, and losing a parent because they chose to leave. In TTM that was one of his main arguments with Rayla. She tells him he doesn't understand anything, he doesn't understand her and why she's so stuck in what happened to her parents (including Runaan), because she didn't know what happened to them, the only thing she knew was that they left and never came back. And Callum does know what happened, they were killed. He has closure, Rayla and Claudia do not. In addition, Callum can't get to Claudia, is because she also has manipulated his feelings and betrayed him and Ezran. She's also collaborating with the person Callum is more afraid of.

All of these people have met Claudia and may have conflicted feelings about her. Rayla may be able to see her situation from an outside perspective and still empathize with her because she has gone through it too.

As I said before, Claudia doesn't have closure, she returned to Katolis looking for Viren and looking for that closure, but finding him death only altered the wound his leaving made. In this same episode (609), Rayla gets the closure she needs to let her biological parents go. Now that Rayla has that she can help Claudia get that too.

I think this scene of Rayla making Claudia understand she's wrong, can parallel the scene with Esmeray in 605, where Rayla understands it and calms it down, she achieves that since she's able to emphasize with Esmeray, they both lost people they cared about, but Rayla makes it remember that even when their are gone their love persevere. With Claudia, the writers could use the same formula.

Conclusion:

Rayla is the one who can make Claudia realize that what she's doing isn't out of love, not anymore, is out of revenge. Rayla knows it and understands it because she confused love with revenge too, and she admits it in S4 ("We had something so special, but I became so obsessed with revenge that I risk losing the best thing I ever had...")