About 80 million people have an ax to grind with Trump. Only a few of them are prosecutors who were literally elected on a promise of prosecuting him. That changes things, in my book. The correct way for him to have handled this would have been to follow through on his promise and also avoid his bias by appointing a special prosecutor with a very high budget to do the investigation - like the federal investigations before.

Also, believe it or not, prosecutors have strict ethical rules around being "advocates for justice" rather than trying to get their guy, and the hint of bias actually does mean that Trump's lawyers can get this charge thrown out on those grounds. It is actually true that on some level {prosecutor is political} == {no crimes he charged can be true}. The courts in the USA understand that to a degree, the process is the punishment, and so prosecutors can also get in trouble for nakedly biased prosecutions like this. This is different than civil litigators, who are free to be as biased and litigious as they want.

Personally, I would have had no issue if he had found some actual, serious malfeasance. In fact, I was hoping he would find some serious malfeasance in the Trump organization given all the other shit we know they did (but couldn't link back to the big guy). But no, the best he could find was Trump's accountant possibly misclassifying an expense on a disclosure form.