I'm glad that I'm not the only one who doesn't understand pokemon
For example, in Final Fantasy V (which came out 3 years before pokémon), a character could already catch monsters and have them battle against others. Many games already had a collecting element. The exchange/trading might be new though, as well as selling the same game twice, with only a few differences between the two (to encourage exchanges… and boost sales).
Pokemon Red, Green, and Blue are the number two Game Boy video games of all time. Behind Tetris of all games. This is a pretty extreme reductive statement, akin to calling Super Mario 64 "just a 3D platformer."