The Social Security Trust holds nearly $3 trillion of the US debt via Treasury bonds that pay about $80 billion in interest each year.
All of the $80 billion is now used to pay benefits and no incoming taxes can buy more bonds because all the taxes are also used to pay benefits.
All those bonds will be redeemed by 2034 or sooner to pay benefits. Of course, no more earned interest either.
Doesn’t that sound like a problem to be addressed before talking about increasing the benefit promise?