Going out of his way to say his freezing would not work on her when it's a DeS spell and involved him actually hitting her with it before the freeze is a crucial detail. If it was as effective as people on here think, it would have been mentioned. And this is me referring to people believing that it gives him a HUGE advantage over her and guarantees him a win. And whether he agreed or not means nothing since at the end of it all he shared the same belief and believed that it would work on her as it did Skullion. Skullion was slashed with it then frozen. In order for him to actually agree that it wouldn't work on Mirajane he would have to remember what transpired with Skullion i.e. DeS magic. If it was just ice make magic I'd agree with you however the fact that it is DeS magic raises the question regarding how effective DeS magic is on her and if it's as it was believed to be.
Gray has been hyping Mira and even Skullion. He clearly thinks she's stronger and mentioned them both together. Even if he begrudgingly thinks so and wants to get stronger and would end up beating him, in the moment he has complained about having to deal with both of them and excluded Elfman and Madmole. Add in the fact that we have actually seen Gray lose to Skullion after trying his best DeS spells and we can deduce that Skullion is stronger. He wouldn't rank him with Mira after losing to him if he didn't at least think that the guy was stronger for now.
You see the issue is that you are making a false equivalence between Gray's current state and Mira's current state. They are both arguably not at full power but Mirajane is injured significantly and has just now finished fighting with someone who beat Gray for a significant amount of time. It's not that oh well Gray is not at full strength so if he beats her it proves he's close in power or greater than she is even when they are both at full power. That's clearly false.
There is no comparison between Gray right now and Mirajane in terms of injuries and exhaustion. Gray even said she's quite injured and we actually see this. All this is dishonest and an attempt to somehow save Gray from apparently being held as weaker than her which right now he is definitely portrayed to be. So no, if Gray beats her, just as he hinted, it's because she's quite injured while he is close to full strength.
It is also false to claim that she didn't use much magic and imply that she didn't weaken much or use much power in her fight. Reminder that this man beat Gray low-mid diff and smiled while doing it.
You are creating your own scenario that is not congruent with the manga. Gray and Mirajane are not equally injured nor have they expended the same amount of power. So one cannot do the math and say well Mirajane is at half strength and Gray is at half strength so if they fight now the result would be the same as if they were at full power/health. That's false.
These are not the same:
The bias I am referring to is in response to you mentioning people wanting feats for Mirajane and not Gray and ignoring hype for her and the logical reasons for her losses. And when I refer to past feats I am referring to the general notion online that feats matter but apparently Mira's new feats don't. And even if you don't subscribe to this I don't see how what has happened in 100 years quest so far still convinces you that Gray would beat Mira in a fight while both are at full power just because he has DeS.
Feats and hype place her above Gray right now and the only thread people have to hang on to in his favor is his DeS being very effective against her which he himself has brought into question by complaining about facing her, saying she'd resist his DeS just as Skullion did, saying he expected to fight her now, when she's quite injured.
So what I am saying is that it is too soon for anyone to say that Gray would beat Mirajane in a fair fight because of these recent developments and his very own statements.
