The CRT noise is an actual sound; CRT flyback transformers tend to vibrate at the horizontal scanning rate of the display and that's audible for NTSC and PAL (at around 15 kHz), if you have good hearing.

An LCD shouldn't whine, but some can (bad capacitors, cheap power supplies, or any number of other causes).

You can certainly hear one of my LCD TVs, at least when it's working hardest (mostly black screen). Samsung had a capacitor recall program, but it wasn't that bad while that was active. I've been hoping it will die, but no such luck.