following that logic geno should not be in... i rly dont doubt geno is popular, but to sell the game on he rly wont do it, and this is actually me saying it because i asked my friends when we diskussed characters for the game, and most of them either didnt care for him or never saw him ever before,
so to casual ppl and those who are not so odlt hat they actively played the game, they dont know geno. so as a retro or secret character he would be perfect, but to use him for advertisement i dont think he is the best choice,
also if you say duckhunt was used for advertisement,
duckhunt is a meme, and sakurai choose him for that more or less, <.< geno is not so much a meme, then he is a nieche fan character most ppl never heard of,
to unlock him ingame as a secret would be dope because you are like who the f is that????? the effect would be a tat better i think ( PERSONALY) ( to me i understand why ppl woudl want him i guess)