Big reason why most tech people I know leave Australia, go over to the states make their million and then come back home. Then the ATO has the audacity to want to tax them for their over-seas income well not residing in Australia.
The best and brightest have so many strong reasons to leave, and many will not come back.
The ATO will tax any capital gains at full value if they get half the chance. And they're a law unto themselves, with no independent appeal or way of refuting a decision that they made.
While I have no great love of the ATO, it is a million times better than the IRS.
Of course you can appeal a tax ruling in Australia. If you have done something that is an open-and-shut case of tax avoidance then this might not help much.