I am joining this late, but this earlier posting from Brendan Burgess nails it:
Duke says he is not opposed to them. I am because few consumers could possibly understand their complexities. And those who do would never invest in them.
I have worked in developing financial products and would not touch these products with a barge pole.
The mathematicians who develop these products manage to create an illusion of value which is not supported by the probabilities around the outcomes. But very few people, including most advisors, are equipped to work out the probabilities. And many 'advisors' just want to sell products (and would prefer not to know the probabilities).