Whine:
That's because save from UPSs and high-power devices all chargers, adapters, etc make use of SMPSUs (the small and light chargers, as opposed to the old wall units that would break a window).

Flicker:
In Europe at least, all incandescent lighting is all but banned (In Romania it's about to get illegal to sell I hear), thus everyone moving to gas discharge lights. Minus the CFs that have SMPSUs inside (those whine), they all flash rapidly as the ballast pushes electrons in the gas (so to speak). 60Hz US, 50 everywhere else.

In addition to this, all backlights in panels, TFTs, etc use CF technology which is exactly like the flicker kind except they flicker faster and at higher voltage (making them flicker-"free" and efficient). However, as the gas oozes out with time, gets contaminated by the electrodes, etc, generally age they start to lose their effectiveness and only fully light every few cycles, effectively reducing the flicker from 100-600Hz for CF/TFT to around 50-60, making them slightly flicker.

In addition to that, most "on" and "standby" LEDs are wired into the power supply to see when it's dead, usually via a gas discharge small lamp (orange) or LED with a resistor and a diode. As a result, they are powered directly at mains frequency, thus, flicker. Orange find-in-the-dark light switches are easiest to see.

Add this to the fact that public illumination use 50/60 HZ had discharge (sodium lamps), and you see why it's true.

Yes, the whole world whines and flickers. Welcome to the 2000s.

20 years ago, it was all yellowish from the low-powered bulbs and it hummed at mains frequency. Those a little older know what I mean by this: TV hummed, fridge hummed, the stereo and radio hummed.

In fact, mains is in sync in the whole area so if you had very fine ears, the whole world would hum as the city concrete slightly moved the heartbeat of technology.