There are two different types of IRAs: Traditional and Roth. With the traditional IRA, the taxes on income are deferred. With the Roth IRA, there are no taxes on income.

You are right in that you cannot withdraw funds from your IRA without paying a penalty tax, if you do so before your retirement age. In this way, the funds are not tangible.

However, if you assume that the current power structure is not going away anytime soon, or will at least still be around in 20 to 30 years, and you want to invest in cryptotokens and reap the rewards tax free without engaging in tax evasion, then this is a decent solution. In addition, if you expect a collapse of the USA, the complete devaluation of the dollar, etc., then having assets in cryptotokens in an IRA LLC allows you to have fungibility (in terms of having control of the private keys, approving transfers, etc.) is one way to protect yourself if / when this occurs.

There are other, more ingenius, ways to make the funds immediately tangible. This would require structuring an LLC that is not owned by more than 50% by prohibited persons. In this case, your IRA could own a portion of the LLC (say 49%), and you could legitimately be paid by the LLC for the services you render to it. Obviously, these payments would be taxable income at this point.

The other 51% could be owned by siblings, sibling-in-laws, nieces, nephews, aunts, uncles, friends, or any other entity.