Well, there are so many Presidents in American history that got away with all their crimes, it really is kind of surreal to see one caught on something so trivial. A real "Al Capone caught by the IRS instead of being a mobster" moment.
He’s caught on a bunch of stuff. This is just the first one to get through trial because of the delay tactics of the judge he appointed in one and the delay tactics of the Supreme Court in another and delays associated with poor judgement in the private lives of the prosecution in another triggering delays.
Oh, yes, I agree that he was terminally stupid on how blatant he acted, both in this and the other charges against him. It is just funny to me how stuff like Watergate and Iran-Contra were never really prosecuted in any meaningful way, and it took a doofus like Trump for it to happen, and the first ever conviction of a president being on something like paperwork and financial flows, instead of, you know, treason, abuse of power (I know those ones are still coming up, fingers crossed for a conviction) or war crimes.
These were crimes committed before becoming president, not acts during their presidential term. He defrauded the American people in order to promote himself for office.
While I certainly do not believe it is infinite, there is something to the Trump/Republican argument that the POTUS shouldn't have to weigh being prosecuted after they leave office in every decision they make. I would expect some kind of leniency if there is a strong belief people think they were acting in the best interest of the country. Which certainly would not have been true about Watergate, but as others have pointed out, he was pardoned before he could be charged.