I asked ChatGPT about the definition of common enterprise:
The 7th and 2nd Circuits use a "horizontal commonality" test, where a common enterprise is found if the profits of the investors are interdependent - i.e., if the success of the enterprise is tied to the success of other investors. Essentially, the investors' funds are pooled and they share in the profits and losses.
3: Overwhelming majority of people who buy gold buy it as a hedge against inflation. In the past 5 years everyone I personally know who has bought cryptocurrency was expecting it to increase massively in value (expecting profit). 4: There have been a huge amount of cryptocurrency pump and dump stories where the promoters have benefitted immensely. In those cases it seems pretty clear that those are securities. In fact pretty much anything that isn't a top-2 coin at this point is subject to this sort of behavior from what I've seen.