hey launched ballistic missiles and cruise missiles along side a ton of drones. They had no way to know that the defense would destroy almost all of it against ahead of time.
The defense was Israel, the US, the UK and I think someone else I don't remember. There was no way they were overwhelming all of that, and they knew it. Remember that they warned ahead of time and gave everyone time to prepare for the attack. If they wanted to deal damage they'd at least do a surprise attack.
Again, Iran never wanted war with Israel. They needed to save face after Israel bombed their consulate, but were never after a full blown conflict.