The sound of obsolete technology

Why do films and TV shows continue to use obsolete or unnecessary sounds for technology?

I was watching episode 6 of Dollhouse on Hulu and got really annoyed with the sound effect near the beginning of the episode when the guy turns off his LCD TV. Listen for it. It sounds like a 1970s cathode ray-tube monitor is being shut down. Why is this necessary? Many of us own LCD monitors and TVs (and many more have at least seen one in action). Why do we need the sound effect of a CRT monitor when the object is obviously a LCD monitor? To show how silly this use of obsolete sounds is, one equivalent would be the use of a propeller plane sound when the person sees a jet. However, if it was only this one thing, I wouldn't really be having a gripe, but it's not only the misuse of a CRT TV sound for an LCD TV, it's the general misuese by substitution of sound effects for previous technology's sounds.

It's only been recently that the stupid sound of *bleep* or the like is no longer used to indicate that a computer is doing something. It's only recently that the visual graphics of what is happening on the computer screen actually looks like something that might be on a computer screen (but that's a different issue). As an example of when this started getting really annoying for me, go and watch that admittedly horrible film The Net with Sandra Bullock. It's supposed to be all high-tech for the time. Well... seriously, what was up with those computer sound effects? I saw that film when it went to VHS (yes, VHS), and was annoyed back then about the unnecessary sound effects.

If The Net is anything to go by, it will be close to 10 years before sound effects actually mimic the real sound of the technology. (Of course, by that time, new technology will undoubtedly have come on the scene, also undoubtedly repeating the cycle...)

When I hit "Publish Post" will I have a sound effect that lets the audience of one (i.e., me) know that an action has been committed on the computer and that something will happen on the magical screen? Somehow, I doubt that it will do so now when it hasn't done so all those previous times. Why? Becaust it is not necessary!