The myth of Apple's low tax rate goes something like this. Let's say Apple makes $10B in profits. $5B are profits of Apple US, and $5B are profits of it's international subsidiaries. Apple pays about $450M in state income taxes on the $5B and about $1.6B in federal income taxes on the remainder (35% of the $5B minus state taxes).
It also pays income taxes in every country it has a subsidiary in on the foreign $5B (let's estimate income taxes average out to 20%, or $1B), and ships the remaining $4B to Ireland for storage until such time as US tax rates aren't so onerous.
Now someone looks at Apples financials and sees it paid "only" $1.6B in federal income taxes, even though it made $10B! OMG, they shout, Apple is only paying 16%, no one is paying 35%, our tax system is a LIE!
But in this example, Apple paid over $3B in total income taxes, or 30%. And if it repatriates the $4B, it will pay another $1.6B in state and federal income taxes for a total tax rate nearing 50%.
And this doesn't count all the other taxes Apple pays, from property taxes, sales taxes, VAT, import tariffs, etc, around the globe.
The "double dutch" strategy revolved around how much value you assigned to your IP and moving that IP to tax favorable countries. It's no longer legal or used. What costs and profits Apple assigns to subsidiaries is subject to judgement and audit. But mostly it's just a smokescreen to ignore how terrible our corporate income tax system is and it's rates are among the highest in the world.
Apple pays a ton of taxes. We'd be better off not taxing corporate income, so one can argue it pays too much.