So, follow-up question: are Team Fortress 2 hats securities? It arguably meets all four points: Valve gets money for releasing hats into the TF2 ecosystem, TF2 is a common enterprise, hat speculators expect to make a profit through simple capital appreciation, and the hat owners rely on the effort of Valve to develop TF2 for their profits.
In game digital assets is an interesting hypothetical. Whether or not it satisfies all the prongs of an investment contract analysis is less important than the overall size of the market. I think if blockchain tokens were doing daily vols similar to Team Fortress 2 hats, that the SEC would have never felt the need to comment. But that's just conjecture not anything you could hang your Team Fortress 2 hat on :)
Technically, I'd suggest the answer is yes. But there isn't enough money involved to warrant regulation or for a tax department to do the diligence to collect. Valve paying corporate tax on the hat sales is good enough.
