So Robin, Lucina, Mewtwo, Lucas, Cloud and Bayonetta - and practically the entirety of Smash Ultimate's reveal - were "very lucky" then? I say Smash Ultimate's reveal included, because look at practically every reaction. Everybody never knew about the 4chan post and when it was brought up, it was after the reveal and/or brushed off because it was a 4chan text leak, which happens very rarely.
Here's the thing; we're living in a different era of Nintendo where back then, they didn't have Directs. That's why the Brawl Dojo was the go-to place for sending and getting first glimpses at pertinent information like character reveals, stages, etc. Now? Why have it when you can put it in a Direct, or announce it on Twitter? Smash Ultimate already has made a sentiment of making the blog out to match up with the "Everyone is Here" motif, so I don't see why people are complaining when this sentiment has already been made practically beforehand at E3.
Honestly, if people didn't become gatekeepers and misconstrued words during this part of the hype cycle, we wouldn't be in this predicament. I'd actually rather go back to talking about chairs and Goku.