But nobody is talking about "forever." We are talking about "for a time," perhaps three months or so, during which people who are infectious are able to be identified and quarantined, and during which other protective measures are able to be developed. Then we can look at a loosening of restrictions, with the sorts of measures you suggest, until we're able to look at a vaccine or other paths to relative safety.
(In my state there's serious discussion of complete elimination as a possibility, but that's part of the benefit of living in an island nation, I guess; we can lock down our infections folks, close our borders and be relatively safe).
I reject your characterisation of those with whom you disagree as hiding or fearful or lacking trust in God. I'm able to trust God to be with us even in these abnormal circumstances.
Just to shed a little light on this subject, here in the US (I don't know about Australia) we have come to realize that very little from our authorities can be taken at face value because we get conflicting opinions from politicians, conflicting reports from media and statisticians, conflicting safety measures from governors, and it sometimes seems that everyone has an agenda and some scheme to make money off this whole thing or advance their own political dreams. So it doesn't make sense for the American church to simply follow what we're told without a healthy amount of skepticism. For example, a church meeting in a parking lot (never leaving the vehicles) in Mississippi was ordered closed by their governor. Why? There was practically zero chance of transmission. At the same time grocery stores are still open, hardware stores are open, they're trying to re-open daycare/kindy in my state (though we all know children can be silent carriers), liquor stores were deemed essential after first being shut down, food processing plants have to remain open, hospitals obviously are open, I even known an ice cream shop that never closed it's doors. so the whole thing feel very unbalanced and rather unfair, especially since the Church is supposed to be a place of refuge for exactly these kinds of times. And online just isn't a sufficient replacement.
The government never ordered churches closed but strongly recommended it and then said no more than ten people are allowed in one place at a time. But last time I was out getting groceries, there were a lot more than ten people inside the store... So if we aren't going to apply the guidelines everywhere, aren't we just fooling ourselves? It will never go away as long as there are compromises left and right.
If it had been up to me I would have given everyone a few weeks to prepare and buy essentials and then ACTUALLY shut down the country for two weeks. No hardware stores, no grocery stores, no pharmacies, no parks or trails. Only hospitals and emergency services (I guess including people like linesmen or plumbers). But instead we made way too many exceptions, and so it really hasn't been successfully contained at all.
One other thing we really did poorly as a country was focusing on states instead of geography. Does it really make a difference that a town on one side of a state border is shut down while one on the other side of the border is all open? Not at all. Unless no one is able to travel between states (which hasn't been the case most places) then focusing on states instead of geographical areas is a faulty way of seeing this.
And international flights continue to come and go... Ugh. Mismanagement at it's finest.
We need to respect our authorities as Jesus instructs. However, in this particular situation I'm not 100% convinced the government didn't ask us to do something unbiblical.