As someone who's studied facial expression in cartooning and tried to track down how that's done through face muscles, this tracks.
Not only that, it is hackable, and somewhat mutable… and I think that can reflect back into one's general attitude on life. I'm going to share some personal notes on my own face hacking done to serve my purposes as a youtuber and open source coder…
The key phrase here is, "The highest predictive power was afforded by head orientation (58%), followed by emotional expression (57%). Liberals tended to face the camera more directly, were more likely to express surprise, and less likely to express disgust." People will respond to you based on what your face is doing, and be more or less favorably disposed to you if you 'match' where they're at.
Guy Kawasaki's on record as trying to maximize his ability to Duchenne smile (crinkle the outside edges of the eyes as your cheeks go up) in order to better influence others. You can make special efforts to dry your skin there, the better to form heavy wrinkles that can come into play, signalling affability and well-disposedness as a proper Duchenne smile would do.
But there's another area. If you fret a lot, or glower, your brow comes down and wrinkles form where your brow meets your nose. This signals suspicion, disgust, hostility. My face-hacking involves putting Nivea cream there and on my forehead, keeping that skin more flexible and mobile, for a more open affable look. But if you're targeting a conservative audience you can do the opposite: look at Tucker Carlson sometime. You can cultivate a world-weary scowl and it will increase your trust with people sharing a similar facial expression, and tend to concentrate your viewer's expressions into ones similar to your own (while you tell them scowl-worthy things), so long as you have their basic trust to start with.
This is all very malleable. Very hackable. You can do it on purpose. I don't know if Tucker Carlson does scowl exercises, but I know if he botoxed his brow scrunch, he would be less effective as a political commentator, because he would be telegraphing the intended reaction to his information more weakly.
We're looking at a general connection between human resting facial expression, and human overall outlook on life. I didn't expect to run across this study but I find it absolutely plausible. Almost axiomatic. You can even frame it in ways that appear to favor one political side or the other, but the underlying principle tells us a lot about how political orientations arise.