I'm not sure who the "some" are who argue for this. I've not heard it before. The article doesn't cite any scholarly literature. If there is any, I would like to see it.
The YouTube tourist video is informative, if a bit cheesy, but it doesn't give references.
The format of the Yeshua inscription makes it more likely that it is a dedicatory inscription than a reference to Jesus. The terms "comforter" (1 John 2:1; cf John 14:16 by implication: "another comforter") and "witness" (Revelation 1:5) are used rarely for Jesus in the New Testament, but they are used.
I am not qualified to comment on the architectual and iconographic evidence.
In short, this is an interesting idea, but I want to see more evaluation of the evidence by specialists.
For PaleoJudaica posts on the site of Susya, see here and links and the fourth article listed here.
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