If anyone remembers the build up to Gen 4, new Pokemon reveals were few and far between. They appeared in spin off stuff, had a bunch of rumors, and were just exciting. Also this was before the Nat Dex cut, so every Pokemon addition felt big and permanent.

Nowadays, even completely ignoring the state of the designs, they just aren't that exciting. Gens come too often, and knowing that Pokemon can be easily cut just makes it, meh. Also there are so many retreads of concepts. It's another Grass waifumon. Yippie.