> IIRC like-kind treatment was never made available, with the new tax plan or without.

They never clarified and now they'll never have to.

Like-kind treatment is given to property, with specific exemptions made by the IRS. If the IRS never made an exemption, but it did designate cryptocurrencies as property, then like-kind treatment applies.

Given that cryptographic hashes are the only thing trading in any distributed ledger technology, it doesn't matter what the name plastered on the network is, it would fit existing regulations and case law around like-kind exchange.

Now with the new law change from Congress, the agency or the courts will never have to deal with it if they don't challenge 2017 tax filings.