Scotty Kilmer is a wackjob IMO. He's my vehicle information version of Alex Jones, but Alex is more correct than Scotty to put it in perspective. Just my opinion.
AGM are still just lead acid batteries so they're not "Better" really, they both die at the same rate given the same-for-same. It's lead acid with a glass mat holding stuff in coils instead of sloshing water around. I've got some Optima batteries that still work after 6 years and some that haven't...it's really luck of the draw I've basically concluded. Kirkland/Costco were preferred here and now they went full Interstate, whom probably made the Kirkland brand anyway.
I'm done with Duralast (Pretty much all, not just batteries) as all have failed prematurely over a pretty wide purchasing time frame, just to kinda rule out a bad run. SuperStart hasn't hurt me and got one still holding up in a sitting '06 Cherokee that hasn't started in 2 years, but I assume it's heading south by now.
Something motorcycle guys may remember talking about is that "bad run" thing. The weakest link in a battery is the strap going to the posts themselves. If either of those two thin piece of lead or metal coming from the many plates sitting in acid break the entire chain is done. We'd see a strong battery one day to entirely dead the next and our problem was the vibrations simply broke the chain. Just something to think about if you're seeing a run of bad batteries that are possibly made by the same manufacturer. I was chasing my own tail trying to get batteries to live for a season of riding until that old article came out.