Unfortunately, the Republicans, though they controlled the reins of government for years, didn’t act to “phase them out,” as you say. They grew them.
Why should I believe any of their pretty rhetoric now?
In fact the GOP did act. Are you forgetting the uproar the Democrats successfully caused by their “privatizing Social Security” BS when criticizing President Bush’s proposed reforms?
Legislation was advanced, but ran into Senate filibuster garbage, and there was insufficient support for passage, as a result. All that was able to be managed was the Health Savings Accounts, and some other steps, at that time. At least steps toward a better system HAVE been advanced by the GOP, but until the country sees fit to elect a sufficient number of conservative Republicans or honestly moderate Democrats, we can’t get more than such incremental improvements.