There’s always been much for Republicans to oppose in Obamacare. The law, at its core, raises taxes on the rich to give money to the poor. It adds layers and layers of regulation to the insurance industry. It creates a fundamental expectation that the federal government will make affordable insurance available for anyone who wants to purchase it.
The problem for Republicans has always been that these aspects of Obamacare are popular.
And so the GOP, in its zeal to destroy the law, focused on the parts that were unpopular. Obamacare canceled existing insurance plans, raised premiums for certain groups of people, and pushed families to purchase insurance with high deductibles and narrow networks.