tell that to all of the dangling secondaries that I've seen trailing behind people. Yeah, those are super easy to retrieve....
I had the tkno on my necklace come loose once. I was actually on a course when it happened. If I'd have contined to dive like that rather than doing a crude knot and getting on with it - would it have been my fault or the equipment configuration?
Some people for having a poor attention to detail doesn't mean the system is broken. It just means that someone isn't doing what they are meant to do.
I've also seen plenty of divers not clip off their primary when doing a shutdown drill. I suppose that if they struggle to find it afterwards then the system must be rubbish as well.