Well, lowering speed limits might be too late depending on self driving cars, how soon they will enter the markets. I can see people complaining when they are everywhere, it doesn't make sense for a self driving car to drive slowly.
The problem isn't we are going to fast it is humans aren't smart enough to go over 15.5 km/h, faster than that and the human race's tiny brains aren't quick enough to react.

Lets bring back the man with a red flag. 30 makes sense in European villages (or African goat tracks), in countries with wide roads 30, it's too slow by far.
Safer all round.
Imaging driving across Australia at 70kph. Undivided continuous roads all across the country, oh and slow to 50 for every crossroad. No wonder everyone wants a flying car.

In the Netherlands they introduced 60 and 80 km/h B-roads which used to be all 80 roads outside cities and not motorway. The result: older and unattentive drivers mistake the 80 roads for 60 roads and cause a queue of cars honking and trying to overtake them. All in all much unsafer. This is just another fake excuse to raise the income of speed cameras.

Unfortunately the #slowdown campaign people are very naïve, you could of course set a speed of ten MPH. But people will still die, its those that blatantly ignore the speed limits that are the main cause of speed related death etc.
Speed limits must be set reasonably, their limits are just stupid for a well designed road, you have to way acceptable risk against functionality.
The real answer is to get drivers to drive at a suitable speed for the conditions - big difference between dry road, wet road, icy road!
Roll on the self driving car!

Well said Brian M!! 10% of the operators cause 90% of the "accidents" on the roads because they are incapable of obeying the rules of the road!! So get rid of that 10% until they can be trained to obey the rules of the road and you will get rid of 90% of the collisions, deaths, wrecked cars, etc. Of course the insurance companies won't like that because they will have to lower their rates because so few people will be making claims, the police won't like that because their revenue stream will dry up, the auto makers won't like it because fewer autos will need to be sold at high prices to replace the wrecked cars and trucks, the towing companies and wrecking yards won't like it because it will harm their business, the hospitals and doctors won't like it because they will see fewer patients, the funeral homes won't like it because they will lose business. Just about the only ones who will like it are the ones who already are smart enough to obey the rules of the road, and the ones who are NOT killed by idiots set loose, and of course the family and friends of those potentially lost people!!

Is Jimmy Carter still available?

let's keep the UN the hell out of the US. train better drivers rather than restrict those of us who can drive. outlaw the driver distractions: cell phones, etc.

What a waste of time, money and effort. Accidents are going to go down dramatically as cars get to communicate with each other, let alone drive themselves. We all saw what the effect was of the 55 mph speed limit in the US.
The UN should focus on other matters. It sounds like too many with experience in creating EU regulations have found jobs there.

Everybody should drive on the Left. It would instantly (well, when everyone learnt to drive on the left), lower road tolls across the board. Study's have shown that driving on the left lowers the risk of many types of accidents for various reasons.

20% risk of dying at 50kmh, 60% risk of dying at 80kmh, 0% risk of dying if you look where you are going, are aware of your surroundings and paying attention to them.