It's not going to happen (forcing Australian users to provide 100 points of ID in order to register for a social network). It's frankly a ridiculous request.
The trolls (the people this is supposed to stop) will just get a VPN, pretend they're from overseas and then create as many troll accounts as they like.
Politicians have zero understanding of the IT world, it's laughable that they think these social networks will give in to their demands and even more laughable to think that people won't be able to find ways around it.