>>464495451. Gold Silver set that precedent but they were suppose to be the last games, so Red was suppose to bring things full circle.
2. Red was the only protagonist of Gen 1 for two straight Gens to the point he's the only viably canon protag of Kanto. The others have to share with a female protag who's more often than not more popular, but as to not alienate anyone for their choice, they simply don't reappear after their games and even the dialogue about them is kept gender neutral.