Social Security comes from its own budget paid by a separate tax. When its savings (accrued by that same dedicated tax) runs dry it has to cut spending. It will not, under current law, deficit spend. The only problem to solve there is whether we want to adjust its funding so benefit levels don’t drop in the nearish future.

People bringing it up in discussions of the general budget usually either don’t understand how it’s funded, or are presenting it inaccurately because they want to end it.

This is part of what I meant by "political problem". People see the mainline deficit number without thinking about the underlying stocks/flows of the system. There are feedback loops embedded in this that are unavoidably political (nobody wants to take grandma's retirement money). There's no "founder's mentality" that can avoid this basic fact.