OK, I admit it's not unequivocally not bias. It could be bias. I would just say there could be other explanations, such as a different ratio between non-politic

OK, I admit it's not unequivocally not bias. It could be bias. I would just say there could be other explanations, such as a different ratio between non-politician activists to politicians on either side of the isle and how each slice of the pie tends to monopolize limited attention bandwidth. If three political tweets by Lebron James are algorithmically boosted, and three political tweets by Ted Cruz are boosted, I wouldn't call that bias necessarily even though the metric being studied did.