The companies with billions on the line didn't seem to think Iran's threats to attack ships were impotent.

Their military capabilities are diminished in the short term, but if their ability to impose a toll on the Strait of Hormuz holds then that's a massive win for Iran in the medium/long term. A mere $2M per ship represents 10% of Iran's GDP. They would become the only country in the world to impose a toll on international waters, and they would have established a defensive deterrent almost as effective as having a nuclear bomb.

They took on the most powerful military ever seen and lived to tell the tale. It's hard to spin that as a loss for Iran.