Also, we should check real quick:
Is unsourced/unverified rumors of an actor possibly being cast as Doctor Who really a spoiler?
I'm not sure that it is. It's more or less news. It doesn't have any bearing on the plot of the story itself, the casting of a new Doctor. Although the casting could hint at things that might be relevant to a plot in that Doctor's series, I don't know that people putting out rumors is, in and of itself a spoiler, or that anything's being spoiled by a casting announcement.
Just trying to cut down on the number of black bars, basically.
If nothing from the actual story or in-universe plot is being revealed by this, I'm not sure how it's a "spoiler" at all. We know the Doctor is coming back. It's not like with the Master casting, where we didn't know there was going to be a multi-master story, so Simm's rumored appearance was potentially spoilery due to his presence revealing a story beat. (and that's in the marketing and had a press release so it turns out that casting/knowledge aren't spoilers anyway).
This is maybe the only real given of this entire show's existence: The Doctor is going to regenerate into a different person. I'm not sure that rumors about who that person is are spoilers at all. Or that the eventual casting is a spoiler, either.
Like - it's out of fictional universe/in our real one news. You're going to see it.