While signalling would likely be helped by education, it is also worth noting that it can be difficult for cyclists to do it at speed on a busy road. Remember, they are on the road because the infrastructure does not exist and they are at speed because they have to keep pace with motor vehicles (within reason). Again, proper infrastructure would help. That includes bike lanes that are free of debris and where the surface is properly maintained. Ironically, hand signals are only systematically taught in driver education (some cyclists don't have a drivers license), few motorists seem to know what they are, and not using the vehicle's turn signal is common among motorists.
As for not stopping for pedestrians, that is common with both motorists and cyclists yet it creates more problems for cyclists. Simply put, when there is less than a one in ten chance that the car behind you will stop for a pedestrian it is very risky for cyclists to stop for pedestrians. Again, this is because a lack of proper infrastructure means that cars and cyclists are mixing.
The most important thing to realise is that cyclists pose very little danger to others and will often come off worse in a simple collision with a pedestrian, whereas people in cars are shielded from collisions whilst also posing a much greater danger to others.
What I'm saying is: tons of people commit varying severity traffic infractions all the time. If you think this is something exclusive to cyclists, that is more likely your own confirmation bias. There are a lot more drivers, and a 2-ton vehicle does a lot more damage to other road users than a cyclist, so the ultimate risk/damage to society is virtually entirely from drivers.
These drivers then have the audacity to suggest that cyclists are the problematic rule breakers on the road.