As you have noted yourself this is only really valid for Carol since Wanda was born with her powers. Her contact with the mind just made her aware of them.
And Wanda fought a Thanos without the gauntlet which is still a feat it itself since he easily defeated Thor, Iron Man and Cap with Mjolnir before.
Carol fought against him with the gauntlet but it's important to remember what exactly happened. If you have noticed Thanos need to close his fist to activate any of the stones effects. Every single time he activated one of the stones effects he did so. The gauntlet was built that way. Just wearing it doesn't give you any powers. Hence why Carols fight with him was totally legit since she held his hand open to prevent him from activating the gauntlet in the first place. That's why he had to get creative and remove the power stone manually to deal with her.