I've seen a rise in griefing tools being used as the hangout I run gains popularity and I've had to create a number of automated security tools to combat them so that the peace & comfort of my patrons is minimally interrupted by griefer attacks. The only problem is that due to imposed limitations on various functions, at best these security tools can only intervene retroactively & my patrons are still subjected to these attacks.
If it were possible for me to get information on visitors worn hud attachments without needing them to opt into an experience (and requiring the hud attachment to also be scripted for the experience), then I could prevent these attacks nearly every time by booting visitors wearing items made by blacklisted users and such.
But as it is now, griefers can still get away with carrying out an attack due to the loophole of attaching a griefing tool to their hud instead of their avatar, thus avoiding detection until they're put to use.
Allowing the full use of the llGetAttachedListFiltered() function for estate managers without the experience requirements seems like a fair way to prevent abuse of the function while also allowing for more robust land security tools to be made.