Roll and Maria Renard said:
Yeah it is very challenging. Nintendo should've done it themselves in NSMBWii or NSMBU. There's only hoping for Peach being playable in NSMB Switch or something. Nintendo should take a look at their fans and listen that people want to play as Peach in the next 2D Mario title, they should also look at this mod and what they've done in Super Mario Run. No more excuses. That way fans wouldn't have to work as hard to implement Peach as a mod in more games. Nintendo should be like Capcom and listen to their fans and take fan input just as how Capcom used to.
Nintendo does listen to their fans and implement in things that actually matter.
Like
Switch ports of games they haven't played
Patches that nerf Bowser Jr. in Mario Tennis Aces
Mario Kart 8 Deluxe having a proper battle mode
Getting rid of region locking in the Switch
Super Mario Odyssey going back to playing like Super Mario 64
Developing a Smash Bros. game that has everyone returning
So it's a bit ludicrous to think they don't listen to their fans at all because they ignored something relatively inconsequential compared to suggestions in the above.