... refunded to the importer of record. Not the people the costs were passed to. Essentially turning it retroactively into a tax to private businesses. This is the worst case of all scenarios for the consumer.
How would the government even be able to determine if a business increased product prices due to tariffs vs other factors, or even if the business increased prices at all? What if the product is a loss leader and the company was fine just eating the expense? Or what about a nefarious company who manufacturers their stuff in Canada but used "tariffs" as an excuse to increase prices? What would they be refunded from?