Like it or hate it. Progress is unstoppable. Like the disconnection from analogue to digital. The telecom companies need to free up their phone towers for new faster speed technologies. The only way to do this is to move the technology forward to 3G and 4G.
Telstra and other leading telecom companies around the world such as AT&T etc., are planning to disconnect disconnect their GSM / 2G network this year.
For Australia Telstra will disconnect their GSM / 2G network on 1st Dec 2016. Optus will disconnect their GSM / 2G network a few months after that. Vodafone will also move soon.