It was primarily aimed at getting an enormous cost item off the ledgers of major U.S. employers and onto the backs of the employees themselves (either directly or as taxpayers).
But why should the government be involved — companies used to be able to decide for themselves whether or not to offer health insurance to the employees and how much.
Obamacare is mandating what they should cover — such as birthcontrol — and punishes, i.e. taxes them with prohibitively large penalties if they do provide good medical insurance.
King O is/was never a friend of corporations. The ACA Cadillac Rule is designed to scourge businesses which provide generous benefits to employees. The tax revenue was always destined to subsidize King O's redistribution plan and to punish success. This time, King O really screwed the pooch because the Cadillac Rule negatively impacts union members who boast some of the most generous benefit packages in corporate America.
Why do people think this was ever an item which cost the employers? Ultimately all of the money for ANYTHING the company does comes from the people who buy or pay for that product. No company anywhere actually pays those costs, it is either passed on to the consumer directly, price inflation; or passed on indirectly, through wage stagnation or employee cuts, or cuts to benefits.
But it always goes back to the consumer sooner or later.