If Japan liking Dragon Quest is the only reason that makes Erdrick so likely. Then Banjo seems super likely with all that seems to line up in his favor.
Amazes me how little proof Erdrick needs to basically be confirmed in people's minds but Banjo is not in till they outright say he is in.
Let's not understate "Japan liking Dragon Quest" and put them in the same situations. Japan LOVES Dragon Quest to the point its one of their modern cultural icons. Very few series have that kind of honor and Banjo just doesn't reach those heights in any context.
More importantly though, Dragon Quest is an ongoing thirty year franchise that acts as the granddaddy to all console RPGs. Throughout that thirty year history the series has been distinctly tied with Nintendo. Every mainline title can be played on a Nintendo console, and every main entry also originally released on a Nintendo console except for VII and VIII during Nintendo's more unfavorable era. Most of the spinoffs have also been developed exclusively for Nintendo consoles or seen release on Nintendo consoles. Dragon Quest has even cross over with Mario in Fortune Street a few years back. It has a massive legacy that Smash could represent and distinct ties to Nintendo to this very day with Dragon Quest 11 Definitive Edition releasing on Switch.
When you add all of that up with the fact that Square Enix is already a company working with Sakurai and Nintendo on Smash. If they want to bring Dragon Quest into Smash, they already have a Smash specific relationship established and have spent the past decade rebuilding their relationship as companies.
Compare that to Banjo Kazooie. Their franchise has largely died out and isn't really remembered all that fondly beyond Banjo Kazooie and Banjo Tooie. Both of those games may be astounding 3D platformers, but they weren't quite the same innovators as say Super Mario 64 was. Microsoft and Nintendo have only recently begun to work together on projects and specific releases and the extent to which they will work together is still somewhat unknown. Microsoft has nothing to do with Smash at the moment. And Sakurai has yet to include a Western third party character as a playable icon in Smash. The main thing they have going for them is that their beloved by Nintendo and Smash fans and remind people of the nostalgia for the N64 era.
When you consider all of that, I think it's much easier for people to see and believe in Dragon Quest being added to Smash than Banjo Kazooie, especially when the latter has only just recently even become a possibility. That's not to say Banjo can't be the character to break through many of those issues or anything like that. Just they'd largely be added for entirely different reasons. Dragon Quest would be added more out of legacy and contributions as one of THE big Japanese third party franchises (Which does line-up with several characters that have been picked not for fan demand purposes as much), whereas Banjo relies much more heavily on his status as a fan request and specific reminder of classic era (A fact that has been uncertain even at the best of times).
I was pretty confident Shadow would be an echo alongside Ken and Richter (and Ms Pac-Man). I honestly think the only reason he wasn't selected is because he's not the 2nd natural Sonic rep, Tails is. Whereas Richter and Ken are very natural 2nd reps for their respective series.
Hell Ken is the only character besides Ryu to appear in every iteration of every single Street Fighter game.
I could also see a scenario in which Sega, Sakurai, or both see Shadow as ill-suited to the Echo role and more deserving of an original moveset. I don't necessarily agree with that myself, but I wouldn't be surprised to hear something like that. Also poor Mrs. Pac-Man is kind of stuck in legal limbo from what I've heard and she's more difficult to deal with.
Based on the rumblings from Fatmanonice, Sabi (PolarPanda), King Zell, and other insiders, this year's E3 could be very interesting even outside the Smash bubble. I'm super excited about the potential of Rare Replay and other Microsoft exclusive content coming to the Switch. It does make me wonder what kind of back-scratching that Nintendo is giving Microsoft considering the former Xbox exclusive games potentially on Switch. Is Banjo in Smash enough? It really makes me wonder what kind of deals were made.
On that topic, has anyone had the chance to play Cuphead on Switch? I'll probably pick it up when I have some free time, but I've got interest in the game for sure.
Cuphead is absolutely fantastic. I've also only played the Xbox One version, but I've heard nothing but great things about the Switch version and the game is genuinely one of my favorite games in the past few years. There's so much love and effort clearly on display that you can't help but love it. If you're up for the challenge, the game will push you constantly and every fight feels rewarding once you complete it. Definitely worth making a priority to anyone who hasn't played it.