So now you know. They think you should stop your bike in order to give way.
Where there's a cycle lane, I agree that it creates the lane-change problem and is generally counter-productive for that reason.
However, where there isn't, I suspect that motorists remember their Cycling Proficiency training. This will have taught them to give way, because for an inexperienced child it's the only thing you can do; you have to help them cope with motorists who can't be trusted to obey the principle that the vehicle in front has priority. Inevitably, however, many former CP trainees will have grown up into motorists with the belief that they gave way because it was the law, and that they can now expect other cyclists to do the same for them.
I don't think child cycle training should change, but a holistic approach would mean that driver training would point out the reasons for the earlier teaching.