To elaborate: if the country is roughly split 50/50, it stands to reason that most segments of the society would be approximately the same. That is, it is to be expected that 50% of, say, retired generals, or diplomats, or whatever would be against Trump. Now, if you only watch CNN, you will hear only about those. The same for Fox News, though I can see more "opposite" news there than on CNN (just my personal, anecdotal observation).
I agree that you get more opposition news on Fox. There's a reason for that -- much of Fox is so crazy, so embarrassing, that a few of their talking heads, and probably producers, realize how stupid and crazy they sound, and try to claw their way back to something resembling sanity. I suspect they're looking forward to a time when they may need to find new jobs with other networks, and lying night after night will probably not look good on their resumes, and they'll wind up pitching fake diamonds on QVC.
Look, there's no real debate about the best ways to deal with covid-19, even if there are no "good" ways, there's no real argument that global warming isn't caused by human activity (though there may be all kinds of arguments about possible remedies, if remedies are needed at all,) there's no reason to "lock up" Obama or most other Democratic politicians, even if you disagree with their policies, but Fox never gets off this stuff. I believe that it could come back to bite them in the butt -- the eventually, nobody will watch but a dwindling group of Trumpolas and conspiracy freaks, which would not be attractive to advertisers. And honestly, I don't know of big groups of people we'd generally consider "honorable" -- like retired top generals, or Nobel-winning economists, or epidemiologists, who've signed letters supporting Trump. Maybe they're out there, but I don't see them because I tend to watch CNN...but, I kinda think that they're not out there.