Yes, that's why I said it was possible for an announcement to take place in the future. But how substantial will that news be when everything was just announced? Do they have another game they can announce, or something else major? Inkling was announced alongside Splatoon 2 v3.0 and Octo Expansion, while Isabelle was announced alongside the long-awaited return of Animal Crossing. A big port for DQ11 and its Minecraft-inspired cousin would've been the perfect context to announce Erdrick.
And even if Erdrick wouldn't be ready yet (especially since all we have for Joker is a model right now), neither of those games will be released until July or later. The announcements could've been postponed to fit the development timeline for a new Smash character after Joker.
As far as I'm aware (and there could very likely be information I missed and am not aware of, so if there is, then I am error), the only "ingame evidence" is the "Brave" codename that was datamined, which is so broad as to mean anything. Apparently the term is fairly relevant to Erdrick, so it's possible, but the assumption that it can't be anything else is where I scratch my head. NetherRealm Studios codenamed one of its characters "Shaggy" back in Injustice 2 to throw off dataminers, when in reality we were getting the Teenage Mutant Ninja Turtles, so Brave could easily be a red herring for literally any other character in existence.
All the other evidence (social media posts mostly), in hindsight, was clearly just about the Dragon Quest announcements from today. But because Smash is out and DLC characters are on the way, every single news or hint is automatically assumed to be about Smash, despite there being an entire rest of the industry that's still alive. The way I see it, there's no more evidence for Erdrick than there was Isaac.
As for these "insiders," they were all out in force last year during the buildup to Ultimate, making all these different claims, and only one or two of them actually had legitimate information. And that was during the massive-scale development of the whole retail game, with way more people involved across multiple companies. Now we're in a much smaller-scale stage of single-character development that can be handled more discreetly, and I'm supposed to believe any of these chuckleheads have access to correct information now? I doubt it.
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