She got her limbs and organs replaced, yes.
But she didn't get reshaped into a completely different body plan.
Making a racoon into Rocket is like making a human into a giraffe.
It is kinda worse.
I mean, being given supernatural intelligence, dexterious opposable thumbs and the ability to use them while standing upright doesn't sound like that bad a deal.
That'd be more like giving a human a free set of extra arms or wings. You're increasing his ability to interact with the world around him, not decreasing it.
The whole statement rings kinda hollow because its like Adam Jensen going "I didn't ask for the ability to teleport, punch through walls, inhuman reflexes, shoot missles from my body, become literally invincible, 3D print items with my hands, the ability to recover from any and all injuries instantly, go invisible, brainwash people by looking at them and leap 12 meters in the air."
Yeah you didn't ask for it, but its kinda hard to feel sorry for you after I watch you nuke the 13th room in a row by flicking your wrist.
I think nebula has the same problem with this. We're supposed to feel sorry for her but we don't really see the drawbacks physical or mental, of her augmentation.
All I see when I look at nebula is someone who is literally indestructible, can fly, hack anything and everything and shoot nukes out of her fingertips.
Its basically cheating by giving someone an obscenely powerful set of powers while skipping doing the legwork and pretending they're a drawback which is stupid everytime its done in media.
The only time I've ever seen a character that is basically god despise his powers done properly and relatably in a way that isn't hamfisted and lazy as fuck is with with one punch man's saitama.