OASDI tax is the employee paid portion of Social Security tax. OASDI stands for Old-Age, Survivors, and Disability Insurance and everyone must pay the government OASDI tax. Social Security FED OASDI Tax will impact your paycheck and there is nothing you can do about it. The benefit will be that you will also receive Social Security benefit when you reach the eligible retirement age.
The government uses OASDI tax to pay all the retirees who also has paid the same tax during their working years. This means once you pay the OASDI tax, you will not see any benefit until you are also retired. It serves as an insurance for future years similar to annuities so there is some benefit in paying OASDI tax. However, you are looking at maximum pay of about $7300 per year for each tax payer, which is a steep amount.