Richard, I agree entirely with you on quality. I’m on the back foot with Cadburys products now as I don’t eat anything with sugar in (only 100% chocolate), so can only rely on other who say their chocolate is not as good. There does seem to be a common theme that it has alterd for the worse and it is known that they now remove a lot of the cocoa butter and substitute it for other less expensive oils.
A lot of confectionary manufactures have also been involved in shrinkflation. If you look at the Penguin and Club biscuit multipacks, they are down from eight bars to seven (12.5% smaller) same price.
The original Jacob Club biscuit was in my opinion a classic example of cost cutting and quality loss.