That response has my respect. He'd planned it before. There's no reason an actor has to have public opinions on difficult topics, and he is staying out of it without disowning jkr.
I agree it probably means he has some sympathy with her position, or at least sees where she's coming from because there is no loss incurred by saying something shallow that allows all the pink/white/blue social media accounts to say 'jude says trans rights'. 'jude says dialogue is where change lives' isn't going to do it for them.