Why isn't there a law that -requires- any employer who provides insurance to contribute the dollar amount they would put toward an employee's plan to -any- private plan the employee wishes? Currently you need a fairly generous employer to even offer you a cash 'bonus' for waiving company insurance and buying private. And even then, it's very rarely comparable to what the company would have paid on your behalf to the group plan.
And why are 401ks tied to employers? Why can't employees choose which 401k provider they wish, regardless of what 'group plan' their employer might prefer? Or an easier alternative: why aren't employers required to offer matching into a private IRA if an employee waives 401k matching?
We champion the power of markets in the US, but then we have all these communal, zero-choice, easily-corrupted corners (particularly surrounding employment) that are a huge drag on those same markets. 'Private' insurance and retirement in the US are tantamount to a 'company store'.
Allowing the self-employed to pay unemployment insurance taxes is the same sort of thing in my mind. Why -not-? If they want to pay in what any employer would and their claims to benefits are the same as any other employee, why the hell not?