Blow up a massive facility that was, what, the same size as Endor (?), and have the debris (with hazardous material, no doubt) rain down on the planet would result in an ecological holocaust. You’d think those greenie weanies would’ve spent two seconds pondering that when writing the script.
By that same logic, Alderan debris would’ve struck the Death Star when it blew up.
Perhaps it was far enough away from both but close enough to be in firing range.
You want to talk about movies botching stuff up? How about Terminator? Man comes back from possible future to stop terminator from killing the mother of the futures rebel leader. Man that traveled back in time becomes father of that leader from that possible future. If he hadn’t come back from that future, she would’ve have been the mother of that leader, thus nullifying the entire storyline.