In regarding the recent system update, jagex claimed they supposedly "fixed" the problem with glacors being "too easy to kill now because of eoc".
Taken from the recent system update
-The difficulty of combat with Glacors has been modified.
So my friend and I decided to test what they could've updated.
Before I was able to take 1 overload/extremes to kill 3-5 glacors..

Now with the update, It took me 1 overload/extreme to kill just 1 glacor.

Not to mention, with very good mage gear such as ahrims/akrisae, its taking much longer to kill these now than they were able to be killed before the eoc update.

Average time to kill 1 glacor before eoc -> 1-3 minutes
Now -> 4-8 minutes

Since glacors are one of those monsters that require the difficult quests/high skills to kill, I'd think Jagex reconsider them/see them as different than other monsters. Except they just made them way to harder to kill now.

Less kills = less effigies, since glacors have a really common effigy drop rate.