> information, especially of a biased or misleading nature, used to promote a particular cause, doctrine, or point of view.
Which I think most people consider bad. If the information is true and not misleading, it would be considered educational or informational.
It's the original "no true Scotsman": there the broad definition (Scotsman=person from Scotland) is used to argue for the narrow definition ("real" Scotsman=good and upstanding person from Scotland)
The bias is what would make somebody consider some propaganda good and others bad.
Like - anti-fascist propaganda is good because it’s biased against an anti-human and oppressive ideology.
The current connotation to me seems a result of propaganda from authoritarian states (nazis in germany, communists in the old communist bloc) and the presupposition that the propaganda they pushed was misleading and/or false.