This particular issue is probably due to process isolation and sandboxing. In Tiger, all of those pref panes were loaded into the System Preferences app, and e

This particular issue is probably due to process isolation and sandboxing. In Tiger, all of those pref panes were loaded into the System Preferences app, and each pane could access all the same data as any other. 3rd party pref panes are supported. In Yosemite, each of those panes is its own process. That doesn't excuse it, just saying something about what's going on.