The "Such as" better ways are ones not quite so inflamatory and challenging because this clearly hasn't worked here.
Sirona started the email convo with a question he answered with the answers the JW's have given him, you don't like that and so challenge it wanting him to think more on it, which he doesn't want to, now realising you just want to change his thinking not your own so he's resistant now.
You can't change people that don't want to change, all you can do is upset them, if they ask questions themselves then you answer them. Ironically many JW's make this mistake with family members too basically shoving the JW's faith down their throat till the none JW member backs off completely feeling defensive.
I often used to say that new JW's should be locked away for 6 months from family members till they have mellowed a bit as so much damage is done when they are new and full of the "Truth" and just want to spread it to all they know lol
You find this on the doors if soeone wants to discuss things they will or won't but family and friends are a bit vulnerable as they cannot just walk away or shut the door.
I'm sorry if i sound harsh but maybe one day your brother will come to you with doubts and ask you for the answers you can give him then.