I agree that no gun, unless there is a manufacturer's defect in the chamber steel, causes a kB.
I don't know that I'd say it's a training issue either. Yes, setback can cause a problem, but in properly manufactured ammo setback will take a while to induce sufficiently to cause a kB. It's worth keeping an eye on, especially if you're regularly rechambering a round and even moreso if that round is older.
Generally, the problem comes from ammo; either ammo that has been overcharged, reloaded ammo that has been loaded in a well used or damaged case, or with a bullet that has been seated too deeply or crimped to hard.
It's rare to have an issue with factory ammo, but it can still happen.
Personally, because most of my guns are .40s, I stopped using 180gr ammo because of this article:
http://www.greent.com/40Page/ammo/40/180gr.htm
The link I posted above touches on the high and potentially easy overpressure issues with .40s.
As for guns causing kBs, and specifically Glocks, A) this has changed drastically from 2nd Gen Glocks to Gen4s and Glocks are not the only ones without a completely supported chamber B) Glocks are not the only guns that kB and C) .40 is not the only caliber that kBs.
The issue was big in early .40 Glocks and because people continue to repeat it and it's on the internet which is forever, they carry that reputation even 25 years later.
For as many alleged .40 Glock kBs as there have been, there are probably a hundred thousand that have never had a hiccup.
I will say that this issue does, I believe, occur more often in polymer framed, striker fired, guns than in other designs. I've seen others, including 1st Gen Walther P99s, that had issues with the .40. Not nearly as many as with 2nd Gen Glocks of course.
So, while guns do not cause the kB, the design of the gun may allow a kB in one gun that would not have happened in another.
The problem with that article is that the newest information in it is from 2004 and most of it is from 16+ years ago. You won't find info like that that applies to more recent gun production.