A bus is big enough to see if you are looking at it. If it is behind you, and silent, then you may not know it's there until it's too late.
A 16 year old girl was killed by a bus in these circumstances where I live a few years ago. Thankfully people here didn't blithely accept that she was a dozy bitch who had it coming.
In fact road design experts pointed out that the street where she died was designed in such a way (with dropped kerb) as to suggest a pedestrianised area. Most traffic is not allowed on that street, only buses. So the effect was to lull the pedestrian into acting as though there was no traffic, when in fact the small amount of traffic there was was very dangerous. Not only was it dangerous, but it was almost silent, so another warning of possible danger was missing.
So instead of simplistically (and nastily) presuming the victim of the accident was at fault, a careful analysis of the situation showed that the affordances of the street were such that an accident like that was all but inevitable.
And things were changed. Changed to accommodate human beings and how they actually behave, not how a bunch of pissed off motorists want them to behave.
Refusing to accept even the suggestion that there could be things we could do to make our roads safer and more pleasant for pedestrians (ie everyone) and insisting that everything is fine as it is and people who die on the road are necessary collateral damage seems like willful obtuseness to me.