It's hard to say because the idea is somewhat paradoxical. We can ask what a radical ascetic visionary in general would say or do today. But if we imagine the Jesus of the 1st century returning to the 21st, the problem is that that Jesus would have to realize that he was wrong in ancient times, that the world wasn't about to end after all. So who would knows that Jesus would say now? And if we don't imagine that connection, how would the 21st century version still be Jesus?