Jimmy Fallon showed Donald Trump preferential treatment during his appearance on the show. He was not pressed on any question and Fallon even praised his unpredictability. Other candidates that have come on the show, such as Hillary Clinton, have been treated differently. Although a comedian, Fallon often jokes about politicians, and that was lacking in this appearance. Rather, Fallon was fawning over Trump.
Yes, Fallon showed Trump preferential treatment. It appeared that they were best friends on TV. Trump is a liar and a racist and Fallon is helping to normalize racism and hate across the country. He should be ashamed of himself for allowing Trump to appear like a nice, fun-loving person.
Unless a celebrity host like Fallon is known already for having strong opinions about candidates, it's wiser to stick to the middle of the road, especially in face-to-face interviews. Fallon's job is not to air the issues unless there's something specific the candidate wants to discuss. It's also not his job to make any candidate look foolish. That's dirty politics, not just tacky.
Jimmy Fallon has no obligation to treat presidential candidates in a certain way. His job is to be entertaining and get people to watch his show. He did that with the Trump interview. The late night comedy shows are not the place for hard-hitting questions about the campaign trail. Most of the viewers don't care about that, they just want to laugh.