Writing articles does need active brain functions and thinking. Making constructive posts and participating in signature campaigns need time and thought and reasoning.
Hence they are not passive income - in fact there is no such thing as passive income.
I agree with you totally, I also don't understand why people call it passive income, in order to earn some money anywhere you must do a really good piece of work at the start as nothing in this world is free, thus in order to be able to earn any money a person must spent time, read, investigate, analyze and react fast on any changes, and if you invest time, prefer to call it additional income.
The other thing that they are calling passive income are work in your job with minimum salary every month. this one we can say stable income and we can also called passive income but it needs to work..
For me passive income is that you don't need to do anything, and I agree banks who give you xxx% on your money is passive income, but in this topic as I understood we talk about the passive income in internet, and thus I don't think that any activity in internet can give you money without doing anything.. this is the reason why I prefer to call it just additional income as I need to exchange my time instead of doing something else in real life..