It's unclear how many missiles Iran has left but the strikes on TELs seem to have been much less effective this time around, probably because most of the damage last time was from spies who have now been burnt. Maybe Iran is running low but there isn't really any evidence of this and given there was a long telegraphed run up, it seems unlikely they have less missiles now than they did during 12 day war after 1st day.
What is clear however is that the defense on the US/Israel side is much worse. The Iranians are firing piecemeal, not in the huge Russia style salvos over Ukraine, and not in particularly huge numbers. Yet there are a lot of hits, far more than first few days of 12 day war. That indicates either improved Iranian missile performance (including related factors like moving from GPS to Beidou) or serious depletion of Israeli/US interceptors or both. There is actual evidence of this unlike the assertion that Iran is running out of missiles.