It’s a tax on the US economy. A tax levied by individuals rather than the government itself. An ingenious scheme. Evil, but ingenious.
The stated intention was to replace income taxes with tariffs; and it came with a bonus feature of handing the President a cudgel with which to grant him personal powers and personal rewards.
It's not a legitimate tax.
That's why it taxed the economy much worse than a legitimate President would do.
Refunds to business, but unless they have to refund to consumers it's free capital to importers