Oh good, it's past the 24-hour limit! I'm safe to post without getting a warning!
Taking a look at Steve and how he apparently took 5 years worth of negotiations had me thinking: remember the Doujin rumor? The thing way back in 2018 where rumors of Smash remixes for Touhou songs from various Doujin circles popped up? Well, here's the thing: Love or hate Vergeben, he made claims that Minecraft content of some form would make it into Smash, and stood the test of time for 2 years before eventually being proven true. Looking back at those claims and looking back at the Doujin leak gives me a little hope that this would turn out true.
And yet this begs the question: how many responses to Steve in Smash were there from Microsoft and Mojang from 2015 leading up to Steve's reveal? If Mojang and Microsoft managed to keep Steve under wraps for as long as they had, then no doubt ZUN's comments about Touhou not being in Smash just by thinking about it, is possibly at some level close to the former two.
Then there's the topic of uniqueness: Min Min and Steve have been absolutely DUMMY unusual, and Sakurai has brought up exploring new mechanics after Byleth's reveal. He's seemed to have lived up to that promise with Min Min having two movesets per arm and Steve flat-out terraforming the stage. If Reimu is gonna be in Smash with that statement in mind, Reimu would probably be just as unique, maybe even more of an act of sorcery than Steve. And with ZUN being so loose in terms of rights, I'd imagine the majority of the time would go right to making Reimu as Touhou-like as possible. I mean, Sakurai's gone out of his way to rewriting all the stages just to accommodate Steve's gimmicks, he's going the extra mile so far, and I don't think he's gonna stop.
Now I'm not saying this confirms Reimu, but rather this puts her in a bigger hope spot than in the past.