Most all of the people in defi do, yes. It's happened a number of times now, so you'd have to work pretty hard to understand enough to use defi but not be aware of the risks.

People who interact with non-bitcoin crypto tend to be a lot more knowledgable about the tech and its implications than an average person. So I would say the answer is probably yes.

Ah yes. All the geniuses that are around the crypto subreddits for example. Definitely Turing award level.

I didn't say they were geniuses, just that they were more familiar with the tech and its implications than the average person. Smart contracts have been around for a while and we basically know the scope of the catastrophes that can result from bugs in smart contract code. The DAO hack was years ago. This is not a new problem space