Maybe they did, I’m not exactly sure how much time analysis they dedicate to each and every prospect they filter. Obviously they can’t go to every game or watch every single snap of every single prospect they put grades on.
There are quite a few non productive games that Kincaid had against okish teams that are a little concerning. You usually want to see a 1st round talent have fairly consistent games. Mayer had more 60yrd+ games then Kincaid, against slightly better teams. There were many times Kincaid wasn’t even top 2 on the team in receiving games, where Mayer had more, etc.