There is a big difference between "getting free money forever" and "getting free money for some time" (1-2 years or so, at least in my country). Especially, if you have a family you definitely not want to risk running out of welfare.
There is a difference, and you offer a hypothesis on how it would affect work incentives. And it'd be silly to reject that hypothesis out of hand.
But a hypothesis is just that: a hypothesis, not a fact. There's plenty of existing research on how changing unemployment benefits change work incentives (answer: not too much), but it's also true that longer time horizons might change that answer. That's why experimental tests are needed.