Would I fill the form on my own or just self-report the interest
income on my taxes?
The lack of a 1099 doesn't relieve you of the obligation to report income. My bank isn't obligated to send me a 1099 if my interest is low, but I still have to report it. If a business claims expenses with a vendor of more than $600 they have to issue a 1099. If the amount is less than that the vendor still has to report the income.
According to the IRS Frequently Asked Questions on Virtual Currency Transactions:
Q41. If I engage in a transaction involving virtual currency but do
not receive a payee statement or information return such as a Form W-2
or Form 1099, when must I report my income, gain, or loss on my
Federal income tax return?
A41. You must report income, gain, or loss from all taxable
transactions involving virtual currency on your Federal income tax
return for the taxable year of the transaction, regardless of the
amount or whether you receive a payee statement or information return.
Cryptocurrency platforms aren't regulated by the US government. That was the point of all these virtual currencies. They also claim that they don't have all the basis information to be able to properly report the cost basis. So it is likely that any 1099 you get will not include the cost basis information.
From the same FAQ:
Q45. What records do I need to maintain regarding my transactions
in virtual currency?
A45. The Internal Revenue Code and regulations require taxpayers to
maintain records that are sufficient to establish the positions taken
on tax returns. You should therefore maintain, for example, records
documenting receipts, sales, exchanges, or other dispositions of
virtual currency and the fair market value of the virtual currency.