This is getting into so SJW territory but does every single game that has a marriage system need to have a gay marriage option?
Of course not. It's all up to the creator.
Personally I think this FE business is all a result of Tomodachi Life politics, which shouldn't have happened in the first place.
The option isn't even worthy of an announcement Ninty gave. That's one marriage option of out many others, and sans the benefit of child units.
If you want to make a game with all straight characters, go for it. It's your game. All gay characters? Go for it. Both? Go for it. Other sexualities? Go for it. It's your game, but don't let people push their agendas on you. In the case of Tomodachi Life, they weren't doing anything wrong having only heterosexual marriages in the game. It just wasn't in their vision for the game.
Anyways...
What do y'all think of Marth
keeping his 8 alt costumes, but getting alt characters like Bowser Jr. in the form of other FE Lords, i.e. Sigurd, Leif, Eirika, etc.?