I have a couple of thoughts on this
First, this supposedly patriotic slogan was imported from the US, where it has been around for decades. In this respect, it’s similar to the recent innovation of having a single performer sing the national anthem at sporting events (adopted in the US because The Star Spangled Banner is virtually unsingable). This has displaced the Australian tradition of either standing silently or singing as a group while the anthem was played.
Second, I’d encourage the slogan if those who spouted it were expected to act accordingly. That is, the moment they complained about any aspect of Australia (for example, Muslims, dole bludgers, greenies and so on) they would be issued with a deportation notice and told to find a country they could love as it is.