Undoubtedly it's another cost cutting measure but what's the go with cables these days? What is being sold as flexible mains cable now looks like light duty speaker flex. In fact I have often assumed it to be just that (for the figure eight cable) until I've seen the 250V 7.5A rating stuck on the reel. TPS is just as bad with the new 4mm looking virtually identical to the previous 2.5mm. The insulation seems to be getting thinned down to the point where it's a wonder if the dielectric strength has actually been tested. And as for 1mm lighting wire...that looks only good for doorbell use (secondary side of transformer of course).
I'm sure the conductors in flexible cords aren't as thick as they used to be either, or is it all just an optical illusion?