I'd like the OP to tell us what objective sources of news we should be following.
Journalism is very simple, they report the who, what, when and where, then leave it to the consumer to determine the why. When they try to tell us why, they leave the realm of journalism and enter one of the commentator. That's not their job.
Advocacy journalism is part of journalism. Look it up.
Not when it's portrayed as just news the way most are doing it today. An individual has an ethical obligation to make the advocacy clear up front, not pretend they're being objective.
Does a poster on a message board have an ethical obligation to research something before posting it? Or do ethics depend on the size of the audience?