“Hasn't that problem mostly been solved already with switch mode power supplies that are pretty small“
It would still be useful to make them even smaller. For example, it’s often not possible to use all sockets in a power strip because of the size of power converters. Also, such smaller converters typically are a bit of a hassle to toss into a bag because of their somewhat awkward shape (especially if all other things in the bag are pencil-shoes or flat slates (laptop, tablet, notebook)
A transformer that fits inside an AC power plug would solve both problems.
I think that, _if_ we could build that, most people would start calling the current tiny converters bulky.
It would still be useful to make them even smaller. For example, it’s often not possible to use all sockets in a power strip because of the size of power converters. Also, such smaller converters typically are a bit of a hassle to toss into a bag because of their somewhat awkward shape (especially if all other things in the bag are pencil-shoes or flat slates (laptop, tablet, notebook)
A transformer that fits inside an AC power plug would solve both problems.
I think that, _if_ we could build that, most people would start calling the current tiny converters bulky.