Please watch the video I linked, this is all very much a joke but also kinda not but either way Brian does a great job and it's funny and stuff
Anyway, my added thoughts:
I love the other thing all these truths could point to, that Waluigi idolizes Luigi
He wants the relationship that Lego Batman and Joker have, but Luigi just doesn't reciprocate these feelings, and after so many encounters with Waluigi trying to be important to him Luigi has found that he really isn't a threat
In his Mario Party Superstars encyclopedia page, Wario is said to spend too much time with Waluigi, further proving that they're not brothers because while there are boundaries in familial relationships that's just not something you usually say about siblings, and the alternative I'd like to think of them as for this narrative is best friends
Say Waluigi has.. almost a crush on Luigi, if not just straight up a crush, and if it is an actual crush I think it might work best as a subconscious thing
Wario supports his friend's desire to be with the human asparagus, the two of course hang out normally but also spend a great deal of time plotting how they'll next intrude on the Mario Bros, it's possible they have a romantic undertone themselves but this could be strange considering their place as mirror images of brothers, but that doesn't necessarily make it unusable as a plot device as many love delving into the complex feelings associated with such taboos and it would be less weird because they're not actually related (this is. mostly a joke. so much of this chapter is a joke. but also), but still I'm personally more drawn to the friends idea
Mario was obviously afraid of Waluigi in Mario Tennis, perhaps Mario didn't know much about him by this point, but by Mario Party 5 they are "pseudo bros" which as Brian pointed out means he doesn't mind working with Waluigi, I think it's safe to say that time has passed between the games (Mario Tennis coming first) so by now Mario has come to know him better
It's possible he still has some kind of fearful respect for the man, but I'd like to think that like Luigi Mario has become almost desensitized to Waluigi, though perhaps Mario is less annoyed by him and more sympathetic towards the man, I'd like to think Mario has picked up on Waluigi's feelings for his brother and wants to try and show him kindness
This got long and it's kinda weird to be writing this about fucking Mario characters, but just,
I really appreciate the idea of the majority of Waluigi's personality, subconsciously or not, being a fabrication so he can be something to his idol Luigi, but Luigi just sees him as a minor annoyance
Part of why I love when Luigi pairs up with him in the 2v2 games :)
Also have this comment I found, which according to a reply is a copypasta:
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Also have this thing about his winning animation with the roses (I'll dm the link if u want):
