It'd effectively make insurers (and everyone else who pays for healthcare) one big negotiating block. The weakest payer gets the benefits of scale of the larges

It'd effectively make insurers (and everyone else who pays for healthcare) one big negotiating block. The weakest payer gets the benefits of scale of the largest. One might hope that would push prices down. (for the record I personally just want the simplest thing that's very likely to work—single payer—rather than any complicated poke-the-market-and-pray solutions, but I think that's the idea of such a measure)