To test this I created the following simple addon whose only purpose was to add an entry to the InterfaceOptions panel. I then disabled all other addons and opened WoW.
## Interface: 50400
## Title: TestAddon
## Version: 2.0.50400
MyAddon.childpanel = CreateFrame( "Frame", "MyAddonChild", MyAddon.panel);
MyAddon.childpanel.name = "MyChild";
MyAddon.childpanel.parent = MyAddon.panel.name;
At first I could open and close the WorldMap without error, however once I opened the interface option panel any attempt to open the WorldMap, or any other frame touched by this, threw the following error:
Error: AddOn TestAddon attempted to call a forbidden function (IsDisabledByParentalControls()) from a tainted execution path.
It is so bad that even macros that simply change a frames state (ie /run WorldMapFrame_ToggleWindowSize()) will cause this taint error to appear.
While code cleanup does solve some of the causes of this problem, I don't think addon authors are going to be able to eliminate it on their own. I believe Blizzard is going to have to fix their code by either changing C_StorePublic.IsDisabledByParentalControls() to a non-secure function, or by assigning its value to a variable when WoW loads and just reference that variable in UpdateMicroButtons().
** Update **
To clarify, once the InterfaceOptions panel is opened the WorldMapFrame may open once without error. However, from that point forward any attempt to open the WorldMap will throw a taint error.