When the system detects a substantial change in the Plugin from your submitted entry, it will get removed, otherwise you could build a plugin that did one thing and then change it to perform tasks outside of the original scope.
Usually you know when you have made a change to your Plugin so there is no need to tell you that your Plugin has changed.
Perhaps it was a security concern if the functionality changed substantially and could have been flagged by their algos, not sure. I have had small changes to Yaml which didn’t result in the plugin getting pulled, but the changes to the main plugin program files were also very minimal.