Don’t see how anything you said makes it overrated. Armor Absorption is essentially an anti-crowd stat, nothing more nothing less. It does it’s job damn well.
The fact it’s not of high importance in endgame builds is an endgame thing - enemy physical damage scales high up while your ability to improve armor basically stagnates. Unless build can amass high armor very easy the primary anti-crowd stat becomes high damage and sustain through it. During levelling the damage and sustain is usually not that high so that practice doesn’t really extrapolate downwards.
3.48 is a record of this patch, but archon ofc should be faster a little. I haven’t tested it with celestials (not sure it can kill raveger, but mogdrogen is possible i guess)-it was built just for CR and to show how upheaval is broken