That's correct. Currently mining is considered essential, but...

That's correct. Currently mining is considered essential, but exploration is not (generally, however there are some exceptions).

Mining was the only thing that saved the Australian economy during the GFC (it was helped along with the Chinese infrastructure spending...I am still waiting for that announcement this time around and suspect that is why Iron or and Coal prices haven't tanked during this crisis).

Mining was the only thing that saved the Australian economy from negative growth in the December quarter.

Currently the miners and service providers are managing FIFO rosters (some sites have exemptions, others have workers in serviced apartments on their breaks instead of flying interstate to their families, thereby avoiding the 14 day quarantine each way), but it's getting tough and further travel/quarantine restrictions will force shutdowns/processing of low grade stockpiles with skeleton crews and further job losses. Let's hope that doesn't happen.