I don't disagree. The notion that we should shouldn't sign those player has more to do with not being convinced by the options we have and what they might cost, not that we don't need a RB. Young should have been sold long ago, as he's never been consistently good enough to be a United player IMO. But he's been given another year and we already have Dalot (I agree that he doesn't look ready yet), so I'm preparing for another season with that situation. Atal is a good player and I've been meaning to watch more games of Dumfries and Mazraoui, but none of them are players we have to sign. What I am saying is, ideally I want a player I was as convinced by as I was with Alex Sandro for the last few years. Atal could turn out to be that player.
Hard to tell, who's available and who isn't at Lyon. I think there's a good chance that Fekir moves (there have bee rumours that he will sign a new contract though) and I could see NDombele going as well (Juventus wouldn't surprise me). You might be right, that Mendy could be one too many, but then again, I think, if you make them the right offer, they'll accept. Traore has lost some form and I am not sure, if clubs want to match whatever they would want for Memphis.
Again difficult to tell, as I don't watch him week in and week out, but I liked what I saw the few times I saw Mainz. I think he definitely has the passing we've been talking about a FB needs and he is a well-rounded player, meaning he's isn't defensively suspect or that he doesn't offer enough offensively.