I live in a country where this is the norm. There is a lot of traffic and shit public transport in my town, to reply to OP's queries.
If there is a traffic light, pedestrians obey it: red man, you wait; green man, you go. On roads where a traffic light is needed due to the number of pedestrians/cars, then there is a traffic light.
Drivers behind you see you indicating to turn and they slow down, maintaining sufficient distance to brake should you have to stop for a pedestrian.
Pedestrians don't just step out, presuming cars will stop for them. You wait, make eye contact, ensure the car is stopping, and step out. You teach your kids to do the same.
People on street corners chatting tend to automatically move back from the edge to show drivers that they don't intend to cross. My DC realised very quickly that, when they scooted ahead of me, if they waited at a street corner for me to catch up then drivers would stop for them. They learnt to stop a little before the corner, so that we could cross together. You can generally tell from a pedestrian's attitude whether they are looking to cross.
The rule applies in towns, not in the countryside. If someone's hedge is so big that it obscures pedestrians, they need to cut it. If there is some other danger, zebra crossing markers apply and signs warn drivers that pedestrians may be crossing.
It's really not an issue, if everyone applies common sense and mutual respect. There are a shitload of terrible drivers here, and the rule about pedestrian priority on side streets is the least of my worries, frankly.
Anyone turning into side streets at 30mph is driving dangerously. Slowing down to turn into a side street is not the same thing as driving everywhere at 15mph, as someone here somewhat disingenuously suggested.