I agree that sensors could mean anything, and so could “intelligence data” but just because the positive was not confirmed “It’s a spy balloon” doesn’t mean that the negative was confirmed “It’s not a spy balloon”. Personally I am unconvinced either way and actually don’t care whether or not it was a spy balloon, my point is that the bbc article absolutely does not say that the pentagon thinks it wasn’t a spy balloon.

Also keep in mind the US military isn’t necessarily going to be honest about what they think the balloon is and how much they can discern about its purpose.