As an example of applying critical thinking to this, I would not leap to an unfounded assumption as you do based upon this statistic that "the vast majority of college professors are liberal," let alone assume without support that this "shows up in their teaching". Let's start with the the statistic that 48.4% are registered Democrats.
First, that's less than 50% of the professors, not 100%, nor a majority.
Secondly, are all Democrats liberal? That is the very first question someone should ask if they were looking at this with critical thinking skills. A quick Google search was able to provide the answer. No. We should not assume this means they are all liberals:
In 2019, the Pew Research Center found that 14% of Democratic and Democratic-leaning registered voters identify as conservative or very conservative, 38% identify as moderate, and 47% identify as liberal or very liberal.
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Conservative Democrat - Wikipedia
Is there any reason to assume that Colleges have 100% liberal Democrats? I'd say without hard data, it would probably be safer to assume as cross section of Democratic demographics you see in the main population as well.
Secondly, why do you assume that because someone holds liberal values politically, that this somehow poisons the facts of what they are teaching? Do you think that being a political progressive means somehow that Evolution is embraced because its supports secularism? I don't understand this reasoning. It simply doesn't follow.
In fact, that is reflective of the logical fallacy that tries to discredit someone's point of view, but accusing them of being a "hater" of the other person's views. "They teach Evolution, because they hate God!", for instance. "They teach racial equality, because their are bleeding heart liberal scum", for instance. Again, this is an example of critical thinking being completely
absent in drawing such conclusions.
As I've shown, this is not the conclusion of critical thinking. In fact, there are a considerable amount of other factors that are being completely ignored in just handwaving away these things as some sort of "liberal bias". For instance, I earned a degree from a highly conservative Christian college at the top of my class. Yet, I hold far more "liberal' points of view than they do.
I left them because I couldn't agree with the basis for their beliefs. That didn't come from me going to a liberal college. It came from myself. It came from my own critical examination of their beliefs, as well as deep self-honesty at a spiritual and emotional level. No college professor turned me out as some clone image of themselves. If they had, I'd be a Bible-Thumping Conservative!