When I am driving I routinely check my rearview mirror and assess the following distance of the cars behind me, so I usually know I will not be rear-ended when I am stopping for pedestrians or for any other reason. If I am driving and I notice someone is following too close for our speed I will tap the brake lights so as to encourage them to increase their following distance. If this fails I will slow down to a speed where their following distance becomes appropriate. If they are an uncommonly aggressive driver I might even pull over or change lanes and allow them to pass, I certainly don't want to be rear-ended! That said, even if I were to fail at this, I would prefer to be rear-ended stopping for a pedestrian that would have stopped than to strike a pedestrian who failed to stop walking into the path of my vehicle.

The speed limit is a reference to the maximum allowable speed of the roadway, not the minimum, only, or even recommended speed.

You clearly never have driven a busy four lane street in LA with bicycles and pedestrians mixed in. What you are saying makes sense in theory but nobody drives that way.

I do drive this way, most often in Seattle which has no shortage of the behaviors you're referencing. You can drive safely too because you are in control of your vehicle.

I didn't always drive like this, but I was in an accident that was my fault that totally upended my life, so I made an effort to change my ways. You can do it too, before you get in an accident that sets your life back, or irreparably shatters it...

I recommend taking an advanced drivers education course if you seriously decide you want to improve your driving. A lot of this stuff is covered.

Stopping unexpectedly does not cause accidents, locking down on your brakes unexpectedly causes accidents. In fact, in the US the person who hits you from behind will be held at fault no matter how hard you hit your brakes or why, because they are expected to maintain sufficient distance and attention to stop when you do.

If a light application of the brakes causes the car behind you to slam into you, the fault is with the idiot tailgating you, while playing with their phone.

Nobody's suggesting that anyone should slam the brakes every time a moving object intersects your vector of motion.