It should be considered legitimate to call out agenda seeking, even if you agree with the opinions of the agenda-holder. When creators sprinkle their convictions opportunistically, people will notice that they're being told what to think. For many, that leaves a bitter taste, even if they agree.

There are a few stories were currently popular agendas overlap with reality, such as the story of Alan Turing. You cannot tell his story without also talking about the government abuse based on his sexuality. In those situations, you can tell the story neutrally, and let the audience judge. Obviously fiction is different though.