The blackout started back in January before the US even got involved.
Due to widespread protests and an attempt to crack down on coordination. This chain of events was widely reported.
https://en.wikipedia.org/wiki/2026_Internet_blackout_in_Iran
It definitely ramped up with the invasion. I watched the webcam streams go dark.
Before the US started an open war. US has been involved in a relentless anti-Iranian campaign since before I was born (I'm 55).