So what is a proper way? I have yet to see.
The Tear of Elune was a relic gifted to the Keepers from the Titans that originated from Elune. Pantheons having interactions with one another doesn’t mean one is above the other. After all, Zovaal has needed favors from other forces such as Helya in order to break free from his prison. Does that mean Helya is stronger than the Jailer in his current form? I doubt it. Assumptions, man.
But why is it specifically Demons and Undead? You’re still avoiding how this is any indication she has power over fel. Even then, one random satyr really doesn’t mean anything compared to the nature side of things.
Who cares about the semantics. The idea remains the same. Use, weild, control, whatever. She doesn’t possess the ability to use fel and has never demonstrated it. Again- are you meaning to tell me demons can just uncorrupt each other? This is a really wacky assumption you’re making.
Elune cleansed her soul thus allowing her to return to the cycle. It’s not like Ysera bypassed the Arbiter or anything. Again, another assumption that she has powers over death without it being confirmed.
And I have shown you that this is not a “shock factor” because there are actually things building up to and backing this reveal. Garrosh became evil for really no reason. This is true. Sylvanas went evil after, admittedly, quite a few retcons. Vol’jin definitely died for shock factor.
Where’s the difference? Well, again, Elune has a lot of lore supporting the idea that she is a member of the Life Pantheon, and we are going to learn more about it, and it’s probably going to lead into a future expansion or at least a better understanding of the cosmology. This isn’t shock factor. It’s exciting new information that’s going to expand our outlook on the cosmology, which was exactly the point of Shadowlands’ lore developments.