It took the rushed glitched out beta that was Gen 1 and improves it into a complete game. That’s why so Gen 2 added so many stables to battle mechanics like held items and separate special stats. That’s why Gen 2 had to use a good portion of its own dex space to add relations to lines that Kanto left incomplete. That’s why GSC has an actual post game, rematches with trainers, the battle tower, daily events and more. That’s why Johto feels like a real place people could live in.

The only reason Gen 1 is remembered is because it was shoved in everyone’s faces during Pokemania. Gen 2 didn’t have that luxury since marking had significantly died down.
The only rain