It seems to be a uniquely WT thing, AFAIK. I've been around mainstream Christianity for nearly 50 years and have never heard of this ransom thing*, apart from when I see it being referred to here. Is there an actual verse (or more) they point to that uses that term? Perhaps they've translated a term differently than the way other translations do. Like they do with "grace", for example.
Exactly my thoughts. The "universal sovereignty 'issue'" and the whole ransom, perfect man vs perfect man scale thing is uniquely JW, AFAIK.
I was at a JW memorial at the KH several weeks ago. All of the family except the sister of the deceased were not JW. The children of the deceased were raised JW, but left years ago so their kids have no ties to the religion. As the brother so earnestly shared the perfect man and scale story, I could tell it was not as impressive to the hearers as the brother intended. That's the thing. JW's think they have this special knowledge/message/secret sauce and are so excited about it. It doesn't land like they think it should.
It's more stuff they came up with to fill the literature they were producing constantly for 100+ years.