Yes the ATO can bankrupt individuals. However, businesses are wound up under an involuntary business wind up or liquidation. Certainly, someones financial situation can be investigated and understood under bankruptcy. Consequently, without a transparent disclosure of assets, it can be difficult to gain a full picture of the assets available to sell and pay a debt.
Therefore the bankruptcy trustee would have the power to seize assets allowed under the law. As a result, this includes freezing bank accounts and have the power to investigate your assets and what can be sold. In contrast, the ATO has no way of knowing if you are an individual with a large asset base hidden somewhere.