Yeah

The law that exempts foreign currencies from capital gains is here: https://www.law.cornell.edu/uscode/text/26/988

Look for the part called "Exclusion for certain personal transactions"

There's a bit of legalese to sift through. It calls foreign currencies "non-functional currencies" a lot because they don't function as currency in the USA. Also, the exemption only covers "personal transactions" which are distinguished in other parts of the law from e.g. business transactions.

No

Re: "links for further reading" it is also worth pointing out the IRS explicitly says bitcoin does not count as foreign currency in its opinion:

But their opinion is not law. Taxpayers who judge that bitcoin is a foreign currency (e.g. because some foreign countries have made it legal tender) are perfectly allowed to treat it as such for tax purposes. If the IRS wants to sue you for that, they would have to prove to get a judge to agree with them that bitcoin is not a foreign currency and that you knowingly broke a law by treating it as such.