Trump has been defined as evil and an enemy of the people. If the Democrats wanted a verdict that would discredit him, they would have avoid a jury pool drawn from a county that voted overwhelmingly for Biden. In political tries (which one once very common, especially in the southern states in the Jim Crow), arranging a biased jury pool was a key element in convicting those considered a threat to society (and to a Democrat, Trump is an existential threat to their culture and way of life). Also note that the judge was elected and could lose his job for disobeying the party’s leaders.
I suspect had the trial been in a less biased county (upstate, or at least in Richmond County/Staten Island)), the result would have been different.
No one has ever been prosecuted for such a crime before. In fact, the chief witness was a woman who would have been tried for blackmail in most jurisdictions. Trump is the first person convicted of paying hush money to a blackmailer. Had he been politically correct, he would have been a prosecution witness against the blackmailer.