I don't think people who write topical songs necessarily expect them to last - maybe what Tom Paxton used to call "short shelf-life songs", but they are a comment on the happenings of the times we live in. People have done it for as long as anyone has been writing songs. They will disappear as they are no longer topical, not because they were inherently bad!
Between social media, biased TV reporting and newspaper journalists having their own axes to grind, who is to know what is "false news" or "false false news" or - heaven forbid, no really? - the truth???