This fake leak is tearing this family apart.
Not the first, or the last time this will happen.
There was no offense intended in my post either. However, I do think your post kinda comes off as trying to tell people that your wants for third-party are objectively better than their wants for more first-party.
All of the things you listed third-parties bringing? First-parties could bring those too. It doesn't need to be exclusive. Me personally? I'd happily have the rest of this DLC be things like more Zelda and Kirby than 3rd party content. Does that make my wants objectively better? Of course not, and it'd be a little rude to try and suggest so IMO.
You see, I'd agree with you, but it's just true. Sure, people will be excited if Bandana Dee or the latest flavor of the week Zelda character gets in, but there's a larger crowd that'll freak out if Steve or Doom Guy gets in. Third parties just bring more to the series; they have the capability to draw in mass hype and, most importantly, draw in new fans.
Legend of Zelda and Kirby fans already have a stake in Smash and have likely bought the game by now. Dragon Quest and Minecraft have no stake in the game and haven't bought it yet, but will buy it when Erdrick and/or Steve are announced for the game. With how big and popular those two series are, there are plenty of people who will buy the game solely to play as those characters. Right there you've just sold a game and a pack or pass. You might even get a solid amount of Switch sales from people buying the Switch to play these characters in Smash Bros. (Adding Erdrick
will sell Switchs with Dragon Quest XI S, Smash Bros., and Erdrick's Fighter Pack or the Fighter Pass).
Characters like Doom Guy and Joker, who seem dissonant with Smash Bros., create hype through their inclusion because "oh my gosh I can't believe they did it!" whereas first party characters are just "oh yeah, that makes sense." By negotiating and including these characters instead of first parties, Nintendo drums up more publicity for the game and drives more sales.
Additionally, the inclusion of third parties creates good will between companies that last. Corporate relationships are highly important in the console industry, where third party releases can make or break a console, and with how easy it is to include third parties as DLC (as profits are easier to split) it'd be stupid of Nintendo to not make the most of this opportunity, especially after the failure of the Wii U, which is largely
due to a lack of third party support.
Maybe it could've been presented better initially, but it's a better business move to include third parties. Nothing on you or anyone else for liking first party characters, but third party characters offer more to the series and Nintendo as a whole.