I think when we hear playstation/xbox controller, then our brains maybe equate that with 'toy' and that makes it sound ridiculous and low tech? But I think the technology in it is the same as what you'd use if you were designing your own controller, so why spend a million on designing something you can buy for $50? It's very unlikely imho that this is the part that's gone wrong. They have backups, so I don't think the batteries in all of them failed at the same time.
It might 'sound' crazy, but I think with this part that's all it is, that it 'sounds' stupid, but really the only thing that matters is if it works, has reliability, and backups.