He made his reasons very clear when he reverted your edit. It's in line with what I asked about earlier edits of yours.
SOURCES. You claim it, you source it. Where was she ever explicitly given metahuman powers?
And please don't pull the "go read comics" card. It doesn't make you look smart, it makes you look like an idiot caught in the wrong. Also, do not harass other users on their message wall, or edit their user pages out of spite. Those two are blockable offenses; do it again and you're blocked.
Think of it like this (sorry for the late response), Green Lantern Jordan is the same as saying Officer Jordan. It's a pronoun so it's capitalized. However if you're saying "Hal and the other green lanterns", you don't need to capitalize it because it'd be like saying "Hal and the other Police Officers".
If you're talking about the Deathstroke one, I put something about that on the talk for it. I changed the name before actually uploading the picture, and I didn't realize the file title overrided it until it was too late.
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