There is a third goal, very much related to those two, which you’re not considering. The third goal is to compel insurance companies to cover those with pre-exisiting conditions, and to make it more difficult for insurers to deny coverage or cancel a plan when an insured person becomes too expensive. This part of the health care plan would put insurers in a tight spot, because under the status quo, they operate with a free pass to ditch individuals who cost them the most. It’s important to understand that, if this were the only thing that the health care plan changed, insurers would raise rates. It’s a direct consequence of them paying more - they would charge higher premiums to everyone who has insurance in order to make up the difference.
Understanding that is key to understanding the other two goals. There’s another way to cause the balance sheets to come up even, aside from dramatically raising premiums. You could simply have more people paying premiums, including those people for whom insurance is not a very good deal. With younger, healthier people who currently forgo insurance now paying premiums along with everyone else, the insurers have a group who can give them the money necessary to cover those other unhealthy individuals they were previously dropping. In short, they’re now acting a little bit more like insurers - providing a safety for the rare individual with catastrophic costs. It cannot be stressed enough that they have not been doing that previously! They’ve been denying coverage to those folks, sending them to federal or state plans and costing all taxpayers.
Here’s where it comes full circle, then. Taking the most unhealthy Americans off the government plans, like Medicare, and putting them into the hands of private insurers, saves the government money. The new legislation causes the insurers to behave a little bit more responsibly with respect to these patients, so that they’re not worse off.
The legislation, as the Senate drafted it, is meant to slow the growth of health care costs rather than actively reduce them to below current levels. The opportunity to reduce costs has probably passed, but did exist in the public option.