Both sides of the media definitely have their share of misinformation. The first reports I saw on CNN claimed there was no significant damage and no casualties, but those stories have since disappeared. No retraction, just poof, they're gone.
I did come across an Israeli explanation stating that even after missiles are intercepted, you might still see them falling. That makes sense to me, though I’m no expert. Plus, if 80% of the 200 or 500 missiles, as reported by foreign media, actually got through, wouldn’t we be seeing reports of massive casualties?
I believe Israel wanted to preserve the perception of having an impenetrable defense system and tried to manage the media to support that narrative. Then they realized they couldn’t fully control the situation. While I do think more Iranian missiles got through than they’re willing to admit, I don’t believe it was as high as 80%.