Again, intent does not matter. Saying it does is simply not true.
Interference is not whether the fan tries to interfere with the play, but rather if they interfered with a player making a play on a ball that’s considered “in play.”
And like I said, I don’t disagree with you about their reactions. It’s not their fault. This was a crazy scenario, and I’m assuming that’s why the Astros let the fans stay.
But that does not mean, by the very rule, it’s not interference. If you look at the rule, the only “gray” area here was whether or not the ball was touched in play or in the stands. Intent by the fans does not play into that.
Intent does matter. IF Mookie could have caught the ball and the fan purposely got in the way, that's fan interference.
I think we're actually arguing the same thing ... with different semantics. If the umpire views that the player could have caught the ball and the intent of the fan was to block the fielder ... then it's fan interference (no man's land).
Here's what wiki says (I know ... they are not always right):
"Such interference often occurs when a spectator in the first row of seats reaches onto the field to attempt to grab a fair or foul fly ball. If the umpire judges that the fielder could have caught the ball over the field (i.e., the ball would have not crossed over the plane of the wall), he will rule the batter out on spectator interference. Also, the spectator who commits interference is usually ejected from the stadium. Note that spectators are allowed to catch a ball that is in play when the ball has broken the plane of the spectators' side of the wall. The area where both fielders and spectators are legally allowed to catch the ball is colloquially called
no man's land."
If the yellow line is "no man's land," the fan has every right to that ball as well as the fielder. If no rules were broken, then it should have been a home run. If the fan wasn't ejected, MLB implied no rules were broken.