I have various retirement accounts (e.g. Roth IRA, 401k) that I have no intention of withdrawing money from until I reach retirement age, which is multiple decades from now.
But it seems like the most common investment options for these accounts are very liquid assets that you can sell within a business day or two, typically some blend of public equity and bonds, where the allocation evolves as you move closer to retirement age.
It seems to me that this is suboptimal, because the ability to liquidate these assets is of little use to me until I get closer to retirement age. There should be some sort of deal out there where I could take advantage of the illiquidity premium, that is, the fact that I'm willing to have my money locked down for an extended period of time in exchange for a higher rate of return.
Are there any sort of assets like this that are accessible to "normal" people who don't have multiple millions of dollars?