It’s not like any of these alleged leaks are amazing ideas. Mostly, they fit the same kind of “prediction” model that psychics use.
Look at the massive stage list leaks posted last year, and reposted this year. It consists of classic stages for returning characters that do not already have a classic stage in SFV, and rather vague descriptions of new stages for new characters. This is a very safe bet, because if Capcom adds new stages they’ll almost certainly be either classic stages for returning characters that do not have one yet in SFV or new stages for new characters. What makes this an even safer prediction is that it lists so many stages. There are very high odds of a few “hits”, and any hit acts as (unfounded) reinforcement that the whole leak is accurate.
More Critical Arts and even a second V-Reversal is again a safe bet, particularly since Capcom did give everyone a second V-Trigger. They are also long-standing popular requests, and items that people have been predicting for years. If it happens, it happens. If it doesn’t happen, then people forget about the claim.
Boss Rush hasn’t happened. The claim that you’d be fighting all the NPCs from Cinematic Story mode, that you’d fight against Shadaloo, Neo Shadaloo, SIN, and the Illuminati in the Ring of Power stage, that never came true. Saying that it came true because Capcom released a few Extra Missions where you fight a single round against a beefed up character is rather beyond reaching.
The promised Season 3 Story, again not even a unique prediction, didn’t happen.
The December promise of a “Patch Version” selection for characters was rather unbelievable. It also didn’t happen. But it was the kind of thing that some players wanted to hear, which helped spread the news about that “leak”, before being forgotten as yet another unfulfilled claim. This also “helps” in that it gives people something that they want to believe in, they want to believe the leaks are true.
The recent "leak"s claim of a new V-System are arguably even more unbelievable than the previous Version Select claim, yet this again is what captures people’s imaginations and causes news of the “leak” to spread like wildfire. Look at everything it promises. Combo breakers, Feng Shui Engine/Genei Jin for everyone, a totally-not-FADC, Ultra/Meteor Combos, and possibly more? And this is presumably planned to be balanced against existing options? (One of the alleged V-Custom button combos has its replacing V-Skill, and the not-FADC would replace V-Trigger.)
Maybe some of the “leaks” will come true. Several individual pieces have high possibilities of coming true just by sheer coincidence or careful guessing. But I wouldn’t put any weight on any of it. And even if a few bits do come true, it doesn’t mean the source was reliable.
