it is an example of what is partly wrong with the uk folk revival the emphasis on listening to sounds rather than lyrics and arrangements , and people who are only interested in sounds but not lyrics, are just not getting the music they might as well listen to most pop.
anyway in answer to the OP. NO not every performer is overtly political.
as a perfomer[ i am sure like many others] I decide to have a balance of subject matter in a set and a beginning middle and end to a set, including changes of tempo and changes of keys and hanges of mood and subject
i personally feel that one politically thought provoking song in a set, has more effect than four or five, performance is to some extent about contrast and variety, presentation of politically thought provoking songs is important sometimes it is better to say little and let the song speak for itself, IMO IT IS A MISTAKE TO TALK DOWN OR LECTURE AN AUDIENCE