NOT cope cages!! Definitely not in any way!!
Honestly it will be interesting to see if that helps the M113 be even marginally more survivable, that thing is a tin can
Almost certainly not.
The cages provide a substantial increase in standoff distance. That won't do much against EFP warheads, but that was, in all likelihood, never the purpose.
Defeating lighter shaped charges, as you'd find on a drone or DPICM, is a different story.
They offer much greater penetration, but that effect decreases faster with standoff relative to the charge diameter.
Slat armor doesn't provide a large enough standoff increase to work that way, but it does offer protection against specific types of warheads.
Most importantly, it works against the most widely available, the RPG-7.
The warhead may get stuck inbetween the slats, or the outer cone gets deformed and crushed into the inner cone, creating a short circuit.
I think most versions have a self-destruct, so the warhead will detonate either way, but by that time, the liner itself will be deformed.
tl;dr: Good enough if you're fighting insurgents with 50 year old soviet surplus weapons.
Against anything other than PIBD fuzes, slat armor won't help.
On that note, this article gets just about everything wrong about how and why shaped charges and slat armor are supposed to work.
The blast wave dissipating outside the armor has zero impact on the damage done by the shaped charge jet on the inside.
Once again, "experts" speaking with the utmost self-confidence, but without doing the most basic research....