While he's not what he was a few years ago, Hall is still at 25 points in 30 games. He's on an absolutely dreadful team, with a bad powerplay. Is that partially his fault? Most likely, but the rest of the players for that unit leave a lot to be desired.
I think whoever gets Hall this deadline will be very happy with the player they got.
Also, Hall is not turning 30, he just turned 28. Same as Panarin was last season. He'll get a big deal from someone and will be worth it for probably about the next 5 years. He still has wheels and a good shot. I would not undersell him, he just doesn't have anyone to play with. Hughes is very young, Hischier was hurt for a while, and Kyle Palmieri is a nice player, but he's not a 1st line winger IMO.