I've asked a few questions that got arguments that that the notable claim is non-definite. Does a claim which says maybe or probably X belong on this site?
Yes, there should be some sort of definitive claim that is being made since it is too easy for a question that makes lots of use of "maybe" or "probably" to be turned into a moving target where it is hard to refute or support a claim since exactly what it is keeps changing. The excessive use of weasel words in a claim is usually a good sign that it is not definitive, or that the claim isn't well formed.
It's not that the claim is not definite. The claim is definite, but the claim is weaker than the question you're asking. The claim is "it seems to a Facebook visitor that the site is blocked".
To address that claim, we'd need to examine whether or not it seemed to the Facebook visitor that the site was blocked.