I think you should try to look on the bright side! As @tau mentioned, if the money remains in your accounts all year, it can be earning you interest in a HISA, or reducing your mortgage interest if you keep it in an offset account. It might not be much interest, but the idea of getting one up on the ATO makes it feel more fun, anyway!

Obviously being surprised with a tax bill isn't ideal, though, so you might want to set up a separate, untouchable HISA (assuming you don't have a mortgage offset account) and have a regular automated transfer (scheduled as close after payday as will be reliable). That way you effectively have 'forced savings', with the bonus that you get interest instead of the ATO. A lot of banks have crappy HISA rates, or require you to remember to meet some account activity requirement to get a 'bonus rate', so it's worth considering finding the best one that you can set and forget.

It might sound like more hassle than it's worth to set up an account with a new bank, but I found it pretty easy to do online when it was just a savings account (i.e. not credit), and for the purpose of 'forced savings' having the account with a different bank to your usual one helps keep the account out of sight and out of mind.

Finder has a sortable list of high interest savings accounts in Australia (link is sorted by base interest rate, not the maximum/bonus rate): https://www.finder.com.au/savings-accounts/high-interest-savings-accounts?sort=AUFSA.RECORD.VARIANT.DATAPOINT_STANDARD_VARIABLE_RATE_COMPV2_L+DESCENDING