A retired couple on SS simply gets their benefits cut if one of them dies. The ‘death benefit’ is a token 250$. In many cases the survivor gets exactly half as much money as the couple would have.

The spouse of a young worker can also receive benefits assuming they have children. But, that’s very much a social program effectively independent of how much money the worker had paid into SS though not their income.

Your spouse can collect either your social security or their own if they don’t get remarried. Your minor children can collect your SS until they are grown. It’s nowhere near what you can do with your own 401K.