Although Pokémon Red and Blue helped spawn the biggest media franchise of all time, there are elements of the game that haven't aged well in certain regions, leading to their age rating being increased on the Nintendo 3DS. It's possible to play Pokémon Red, Blue, and Yellow on Nintendo 3DS by purchasing them on the Virtual Console, along with Pokémon Gold, Silver, and Crystal.
The 3DS versions of Pokémon Red and Blue added some new features, such as the ability to trade Pokémon wirelessly with other players. The sequels added even more content, as it became possible to catch a Celebi in Pokémon Crystal after defeating Lance for the first time. The games had some minor changes, with Jynx's color scheme changing in every game from Pokémon Yellow onward, but the experiences were almost identical to the ones on the original Game boy.
The early Pokémon games didn't escape completely unscathed when brought into the modern era. In North America, Pokémon Red and Blue are rated E for Everyone by the ESRB. This is true on both the Game Boy and the Nintendo 3DS. The European versions of Pokémon Red and Blue on the Nintendo 3DS weren't quite as lucky, due to changes in how games are rated.
The Problem With Pokémon's Game Corner
In Pokémon Red and Blue, the player can visit the Celadon Game Corner and play some slots. It's possible to earn coins by winning big on the slots, which can then be spent on prizes. This is the only way to acquire a Porygon in Pokémon Red and Blue and it was the easiest way to get a Dratini. Since the release of Pokémon Red and Blue, the PEGI age rating board determined that any depiction of gambling in a video game will instantly result in a 12 rating. The Game Corner is too big to be removed by Pokémon's developers, as it also contains the Team Rocket hideout. As such, The Pokémon Company had no choice but to accept the 12 rating in Europe. Pokémon Yellow and the Generation II games also had their ratings increased in Europe, as they also featured slot machines.
The PEGI rating would go on to have an effect throughout the entire Pokémon series. The Pokémon games gradually stopped using Game Corners, to the point where remakes of older games still had them present, but they were closed to the public. As such, the slot machines are no longer part of the series. The inclusion of gambling elements in the Pokémon series was likely inspired by the Dragon Quest games, as they are full of casinos and games of random chance. The creator of Pokémon has stated that Dragon Quest inspired the trading mechanic for Pokémon, so it's possible that the slot machines were also a nod to the iconic RPG series.
It's not surprising to see The Pokémon Company remove the gambling minigames from the Pokémon series, even if it was forced by outside elements. The Pokémon series has always been aimed at kids and a higher age rating will seriously influence The Pokémon Company's bottom line, so the slot machines had to go.
Source: PEGI