"If there are no public benefits, workers will have to make do with whatever salary they can get. Additional public benefits make them somewhat more comfortable, so they can be somewhat more choosy about employment, and if they receive sufficiently generous public benefits, they might choose not to work at all, unless they were offered a very high salary to make it worth their while."
It's just a thought experiment, I am not advocating anything in this paragraph. My intuition initially was that getting some public benefits made workers more comfortable, so they would accept lower salaries. To check my intuition, I imagined extending the size of the benefit to extremes in both directions, from "zero" to "very large," simply to make the consequences more obvious. It's not a proof of anything, nor a recommendation of anything.