Earlier quoted context omitted.
> The more I look through this ruling, the more it seems like it is only designed for people who hold their cryptocurrency at an exchange. I think you're absolutely right. The guidance only makes sense through this lens. It's unfortunate that the IRS didn't base their reasoning on the technical characteristics of the underlying blockchains. There is a whole lot of ambiguity as a result.
Nah, it's just up to you to justify the value of the asset when it forks. Frequently that's $0. If it's a meaningful fork, like BTC/BCH/BSV you could easily use the value at listing on the first exchange as the cost basis, as that's what everyone else will do in lieu of a 409(a) type valuation, which of course doesn't exist because crypto doesn't have intrinsic value. It just means more legwork for you. This is also…
Q27. I received cryptocurrency that does not have a published value in exchange for property or services. How do I determine the cryptocurrency’s fair market value?
A27. When you receive cryptocurrency in exchange for property or services, and that cryptocurrency is not traded on any cryptocurrency exchange and does not have a published value, then the fair market value of the cryptocurrency received is equal to the fair market value of the property or services exchanged for the cryptocurrency when the transaction occurs.
If there is not [yet] a published value at the time of the airdrop, A27 seems to suggest that "the fair market value of the cryptocurrency received is equal to the fair market value of the property or services exchanged for the cryptocurrency when the transaction occurs". If you received the cryptocurrency in exchange for nothing, I'd conclude that the fair market value was $0.
(IANAL, IANYL, YMMV, etc.)