I wish it were otherwise, but it does little good pretending otherwise. The graphs tell the story (just lately coking coal has picked up a bit) - it has been all downhill for 5 years now:
Why - partly declining economic conditions (good conditions start a boom up), but also because we have to compete with other countries that were developing their mines at the same time after the boom began. The government propagates the myth that we have something better than all other countries because then we are happy for them to increase taxes etc. (and let's face it, who doesn't like to think they or their country is exceptional in some way)? The truth is that we have as good as any of the other "lucky" countries (but not better), but the price you can sell for depends on how much of a mineral the world is producing. If other countries can sell cheaper than us because we become high-cost producers, we have to accept the lower price to sell our minerals, our profits drop, people get laid off....
And of course governments try to tax mining companies more than other companies when they are doing well. Minerals belong to the States, not to the Commonwealth governments. But when things were good, the Federal Labor government under Rudd attempted to introduce a Commonwealth "excess profits tax" on mining that was not on excess profits at all but just above a moderate amount at that time (banks were making far higher profits but had no such "excess profits" tax). ie, the Commonwealth could not tax minerals so they taxed "excess profits" but confined the tax to the mineral industry - very innovative our pollies. It didn't work for a number of reasons, one being that the States got upset and threatened to increase royalties greatly (some did) - the problem being that the Commonwealth was going to make an allowance for royalties paid to the states (because the rates are different in each state) - so it reduced the slice that the Commonwealth could get after State royalties.
Which sounds good, "tax the *******s" you say, but minerals are a roller coaster industry. Imagine if the price car manufacturers or beef producers could get at times was less than 25% of what they could get at other times, just over 5 years? And governments maximise tax in good times but don't give them any tax breaks in bad times, unlike some other industries. And this impacts on training - companies do provide various schemes and bursaries, but often by the time they have trained up a good large work force they have a downturn and are laying off again (so 457s and labour hire firms are often better for them in terms of flexibility - instant supply of trained people - but expensive and rarely the first preference). This boom differed slightly in that it lasted the longest of any in my lifetime (but other things affected mining companies during the boom - Australia sold its gold stocks because the government wanted the money and the price of gold companies crashed, then the 2008 economic crisis occurred, and although mineral prices remained good there was no longer money to invest in new mines).
Likewise when profits dive, so does any employment they can afford to cut - look at my area of mineral exploration (less dollars spent = less people employed):
Part of the problem with the roller coaster is that issuing of permits of new mines - or even permits to explore for new mines - is incredibly slow in Australia, commonly extending over years. It can take 10 years to discover a new mine, a company spending millions to tens of millions every year with no income, and then 8 years to bring it into production, with no income (varies with the type of mine - more like 2 not 8 for gold because they tend to be smaller mines). Environmental costs as well as time can be an issue, with reports costing many tens of millions of dollars each in some cases (I think $30 million for Olympic Dam extension, that was delayed for ages then abandoned). It was a similar sory with NW SHelf gas that was also canned after years of negotiating. So timing is a real problem - you don't want to be sitting on your hands during a boom trying to get permitting and then finally get production going in a slump when prices are low (all your expenditure when you are earning nothing, all your income when you can earn the least - try buying a new house and then not having a job for years). The government, Greenies and public in general says "let them wait another year while we negotiate, it doesn't matter" - but it does. Olympic Dam finally got the OK as the downturn began and they shelved its expansion because they could not get a return on their investment with dropping copper prices. I don't know how Adani is affected (since there is a bit of an upturn right noew in good coking coal).
Sometimes one needs to look at both sides of the story - yes, companies will get the most they can out of you (but in booms when trained people are short, we do the same to them). And the government will get us both, coming and going, and will spin any story to get what they want (which is probably what they think is right, but isn;t always and the public doesm't know the real issues)......They get their pay no matter what happens