(‘bad’ language ahead)
Reducing the speed limit from 30mph to 20mph reduces the fatality of hitting a pedestrian or cyclist from 40% to 5%. Slower speeds are fundamentally safer on crowded urban roads, and small country lanes – everyone has more time to react and even in the worst case where a collision occurs, the accident is more survivable.
There are those who claim the lower speeds will slow them down – tough! That continually looking at the speedometer is more dangerous – get used to lower speeds. All of the excuses I have seen amount to selfishness.
And similarly the opposition to prioritising vulnerable road users – letting pedestrians cross at junctions, giving cyclists at least 1.5m of space when overtaking, etc. all amount to motorists’ entitlement. You aren’t more important, you don’t pay for the roads, and the safety of cyclists and pedestrians takes priority to your convenience.