That's not paraphrasing, OP; that's word-substitution plagiarism.
I think the same, he is just replacing words not using different words for the same construction, thus can't be considered paraphrasing.
Interestingly enough, I also doubt he was using an automatic tool, I've tried to spin the text with all the text spinners in the first 20 results on google for such tools, none managed to get even close, so de did put some effort into it.
Original:
Why the system is so unfair is not at all obvious and is the source of much political confusion. People on the left think the rich get there through exploiting the poor.
But the reason for its unfairness is not entirely clear, and this in itself is the source of most political confusion. Leftists believe that the rich are abusing the poor.
No free text spinner will manage this.
In his defense, he did say in the beginning that it's now his work:
Jimmy Song is a well-known Bitcoin developer, writer, and entrepreneur. In his new paper, he explains why there is no balance in the world economic system and explains why Bitcoin can solve the problem. You can read this article below
but then why did he change the wording in the text?
Unless the user comes here and explains why did he do that probably will never find out why, as it makes little sense, even with all the desperate moves for merit fishing we're all seeing every day.