As you know, that took place days after their (Irans) retaliation.
From your own source.
Briefing media on operational objective of missile attacks on US bases, IRGC Aerospace Commander Brigadier General Ali Hajizadeh stated that Iran was not after killing anyone although “tens of US troops have likely been killed and wounded and were transferred to Israel and Jordan on 9 sorties of C-130 flights”.
He noted that had Iran intended to kill the American forces, it could have planned high casualty operations to kill 500 US military men in the first step and 4,000 to 5,000 others in the second and third phases within 48 hours.