Here’s where I disagree:
The reasoning you’re using against Waluigi is a thing people used against Steve just because they didn’t understand the people who loved him since, while he’s treated as his own character in some official media (not much unfortunately, mostly few news things, few tweets, and some official Instagram art as well as some info that may not be set in stone i.e. that one thing about Steve and Alex in a Lego Club magazine) and in plenty of fan media, is usually the default skin and mascot alongside Alex with not much personality beyond actions/body movements. I don’t think the sales matter in this case.
The meme thing could also be said of Sans due to his immense meme popularity where some people only know him or first heard of him from the memes before playing Undertale if they did, seeing this funny skeleton man beat up a kid to funny rock n’ roll music.
I’m not arguing the sales or how beloved the games are or whatever, I’m talking about the characters themselves, and I personally think it’s silly to pretend Waluigi has no popularity and that the memes are purely jokes when, while yes memes can be used to dunk on/hate on things for laughs, are also usually used to make funny stuff for things people (including the meme creator) like/derive funny from popular things/characters, making the fans of those things/characters get good laughs and maybe make more funny stuff with their favorite things/characters…and the funny stuff continues.
Also, if memes are derived from hate, they usually don’t last long because few people beyond trolls and very rude people (a minority) care about them, so if anything is getting longterm funny memes that don’t even seem hateful at all then it should be pretty clear people like them or at the very least the funny aspect about them (likely loving or eventually loving the character themself even if just for funny stuff anyway), especially if those memes are widely loved as is the case with Waluigi. Pretty much part of what
Verde Coeden Scalesworth
said about memes/popular characters.
And I get there are reasons to believe Waluigi may not get in. I just focused on the meme thing because that’s the only thing I saw you using against Waluigi and I didn’t understand it at all.
(edit: also if we’re arguing sales we could technically use the Mario spinoffs since Waluigi is a loved playable character in those)