Yes, libertarians generally oppose social insurance, compulsory savings and government safety nets as tyrannical collectivism, though not all libertarians subscribe to that idea.
Economist Friedrich Hayek supported a universal basic income (UBI) for the disenfranchised and endorsed compulsory insurance and retirement savings to prevent citizens from becoming social burdens.
In his 1962 book Capitalism and Freedom, Milton Friedman proposed a negative income tax (NIT) which offered refundable credits benefiting taxpayers whose income fell below the tax liability threshold. The NIT system acted as a social safety net and an alternative to the existing welfare/tax system.
Though plausible and articulate, the proposed alternatives to social security and social welfare ultimately undermine a core tenet of libertarianism that opposes wealth redistribution and state-mandated investing and savings.
The principled alternative to social security is endorsing profit-seeking company benefits programs, private retirement savings and investing, and private charity, ensuring all monetary exchanges and handling are voluntary and with individual consent.
Libertarians who oppose social security typically support a gradual phase-out, implementing a careful strategy to dissolve social insurance taxes while still providing allocation to rightful recipients and beneficiaries.
For more information see, 'Are Libertarians Against Welfare?'
