Chu, no idea if the local telco uses protection. I'd guess they are. My own little 6 line, 12 station telephone system has nothing on it unless it's already internal in the power supply.
But again, there you're talking about 1000's of feet of wiring that's exposed, strung from telephone pole to telephone pole. THat's subjected to lightning strikes, static electricity, etc. I'd expect them to put in some kind of protection... so I don't have to.
A couple of last points to counter AV: I'd guess that the money I'd spend on surge protection to 'properly' protect against surges would far exceed the time and material spent repairing stuff that could possibly blow up at my place over a 25 year period. But again, if I'm gone for long periods of time, I unplug my equipment.
AS AV says above, a lot of specs are misused and not properly understood by end users never mind manufacturers. That's a problem right there.
Let me throw a surge protection system that I personally would think would work, but I don't know how practical it would be. It's based on a decades old circuit called the crowbar. Funny enough, I haven't seen the circuit used in consumer electronics, but have seen it in a Carver pro amp, an entry level one, the PxM900.
What the circuit does is sense an overload/overvoltage condition, and that then triggers an SCR, a very fast silicone switch. THe SCR is placed across the AC or DC power supply lines, which are shorted out in the case of an overload condition. That then blows the power supply fuse, and it disconnects the power supply from whatever it's driving.
So off the top of my head, how about we change all main breakers in a house to fuses, as breakers are very slow acting compared to fuses. I'm just talking the 100/200 amp mains, not each 15-30 amp breaker in the panel.
Build a crowbar circuit that detects any voltage spike say over 140 volts that are long enough in duration to potentially damage equipment. THe crowbar circuit then blows the main breaker panel fuses.
Disclaimer: I haven't researched this at all, this is off the top of my head that could provide a solution that is effective, cheap, and will alert the end user that 'hey, there's a problem here'.
The Carver amp used that system in that low end amp, and it worked quite well. Mind you, the damn crowbar SCR shorted out, so I went through 5 fuses before I realized that it was the protection device itself that was bad..