RE4 was a great game but the plot was probably the worst
Not the story you follow in the game, it was actually pretty fun, but the way Leon randomly faces a different kind of outbreak totally unrelated to Umbrella's viruses, I mean if he was sent to investigate the "Las Plagas" it would've made sense, but he came for a totally different reason and it makes it seem far-fetched.
Also the way Saddler wanted to keep Ashley to get money was stupid, why didn't he just let Leon rescue her and bring her home, he had no knowledge of her having a parasite, their plan would have worked and he would have controlled the president.
Also the villains were ridiculous for a RE game, that Elf Salazar, why would they put and Elf on a RE game? he is an Elf, look at his ears. And the way they dressed they looked like characters from Lord of The Rings or something.
https://www.youtube.com/watch?v=UA5O_0Ufjwc