But... so many people are practically forced to exceed the limit just to keep up with the rest of the traffic that's already blowing past the limit. If you force a few people to go at the limit, that's frustrating for everyone behind them in the best case at best... and I imagine possibly even more dangerous in the worst case, no? If they're going to enforce then shouldn't they try to enforce it as widely as they can…
No. No one is 'forced' to exceed the limit, not remotely, and there are plenty of drivers who, for a variety of reasons, drive at or under the speed limit (many large trucks, for example). On a highway, driving slow in the left lane is not good, but doing 65 in a 70 in the right lane is perfectly fine.
You never get tailgated when you go too slow? People do it all the time and it's dangerous as heck.