Iran using bulldozers actually does tell you what happened.
This isn’t a figurative coverup. It’s physically a coverup of evidence.
One theory I had initially and still believe has at least some merit is that it was a mistake. Two possible minor variants on this. Call it 1a being a human in the loop got jumpy or buck fever and intentionally fired at something he mistakenly believed was a threat. 1b being someone mis-configured the system (call it fatigue, shift change, outright error) and in that particular mode the SAM system fired on an air target because it wasn't squawking the right modes and codes.
If it wasn't an accident of some sort, then it was intentional. Again a couple of variants on this. One is that it was ordered/executed by someone in the Iranian chain of command who sympathizes with the protesters and opposition and is trying to get world opinion even more against the Iranian regime. A bit extreme but, that is the land of extremists.
However, that is a little obvious and could backfire on the anti-regime opposition. So yet another theory is that it actually was the Iranian chain of command, doing it intentionally, and then planning on blaming anti-regime sympathizers. ie. a "false flag" operation.
If we're going to believe this was no accident, that it was intentional, then I would tend to believe that last theory. No-one in the chain of command is going to kill a couple hundred civilians in such a public way on their own authority. Even if it is never publicly admitted, the guys in power would know what happened. That's a death sentence for who-ever ordered/executed it - unless they had top cover and approval. So I think it is unlikely a sympathizer did it intentionally to embarrass the government because he would fail. He would be publicly executed, both losing his life and pulling the blame off the regime. So I believe it was either an accident, or a coldly calculated move by the regime as a false flag operation.
Either way, the bulldozers tell us the Iranians know it was one of their missiles that brought down the aircraft. They're trying to cover that up so that they have options on how to spin this, maybe sticking with the mechanical failure story, maybe busy selecting/framing a scapegoat...
I don't know, what do y'all think - are they scrambling to clean up any evidence, or does their response seem almost pre-planned? That could be a good clue as to whether this was an accident or a coldly executed plan...