Author here. I've written a couple of articles about counterfeit chargers. You are correct; people cut every corner possible to make a counterfeit charger that looks exactly like an Apple charger. (If you buy a $3 Apple charger on eBay, this is what you're getting.) The power quality of the knockoffs is awful. They also ignore safety, so the fake chargers occasionally kill people.
For point 2, I also wrote an article in the IEEE Spectrum about the history of switching power supplies and how we ended up with such tiny chargers.
Links: http://www.righto.com/2012/03/inside-cheap-phone-charger-and... http://www.righto.com/2016/03/counterfeit-macbook-charger-te... https://spectrum.ieee.org/computing/hardware/a-half-century-...