The reason is because the techniques noted have transcended 'propaganda' and just become 'argumentation'.

c.f.: socialism as a blanket assertion of something being bad without evidence.

edit because I forgot this story...not long ago I ended up in an online argument with someone that I really shouldn't have been about what communism is and isn't (yeah...). Their literal claim was that 'communism is a form of socialism' and they claimed that was evidence that communism is bad, because socialism is inherently bad.