eBay is continuing its push towards emphasising fixed-price goods from professional sellers, but that doesn't mean the process always goes smoothly. Back in February it announced plans to make it compulsory for all sellers to specify handling times and return policies. That was supposed to happen in May, but has now been delayed until August.
eBay says that the switch is still happening and is encouraging people to include those details in listings even though it isn't yet compulsory. Having clearer rules for buyers should make purchasing more attractive. However, having to create handling and returns policies is certainly likely to discourage casual sellers, if they haven't already been disenchanted by being pushed into competing with overseas listings. (Note that you can in theory specify a "no returns" policy, though that wouldn't override your obligations under Australian consumer law.)