It would be unreasonable (& annoying) to have different speed limits for every different corner/stretch of road. There's also considerations such as the weather & lighting conditions to take into account (& while I have seen signs on motorways for variable speed limits based on those in Europe, you cannot expect every case to be covered).

The problem of speed limit overuse (recognized even by our officials) is a lot smaller in western Europe, if you got your experience from their roads.

I seriously doubt this. It's a speed 'limit' not a speed 'target'. I can't fathom how you could think 'sign says x, I'm sure if I go that speed I can get around this sharp turn safely'. How strict were the driving tests where you learned?

Please be aware that the rather strict driving test in the Netherlands means that you are trained for at least 40 odd hours, or let's call it 60 hours on average, to drive at the speed target. Going too slow means you're unable to handle the traffic, and going too fast is illegal, so this strictness can instruct people to drive at the speed target.

Yes, I did name them targets, because that's what they're used for. It looks like a target, it acts like a target, it's called a target. Legally, they're limits, but I don't think you'll ever see many people driving at the limit. Always at least 1 or 2 km/h faster.

Same experience with the speed target/limit in the Czech republic.

In many European countries, there actually is a speed limit before almost every sharp turn that's in or near a bigger city, and thus people begin to think like this.

Not only there are speed limits before sharp turns, but unnecessary small limits in regular turns or on straight motorways, which makes people go over the limit even when the limit makes sense.