I can tell you more about your second question than your first, though it's through a source that will likely give you more detail on the first.

Danish sociologist Gøsta Esping-Andersen wrote a great book called The Three Worlds of Welfare Capitalism, a really triumphant book, hugely important for anyone writing about the modern welfare state. Here's the Wikipedia page. He identified "welfare capitalism" (this was written during the twilight of the Cold War) came in three different forms: liberal, conservative, and social democratic. Britain, the USA, and the rest of the Anglosphere were "liberal". This is in the economic liberal sense, not in the politically or socially liberal sense. Finland, Denmark, and Sweden, meanwhile, were part of the social democratic "world", as were one or two other Northern European states. Just for completeness, the Conservative was the partially family based policies of much of continental Europe, especially the historically Catholic majority countries.

Esping-Anderson traces these divergent developments to the post-War period, particularly the 60's and 70's (though I'm sure he could trace them further back). I'm trying to get his language correct, because he clearly chose it very precisely. I'm relying on this summary for quotes:

The liberal Anglosphere model was means-tested assistance, modest universal transfers or modest social-insurance plans”, “Benefits cater mainly to a clientele of low-income, usually working class, state defendants.” It was very much about providing a minimal level of assistance for a minimal level of tax, and really just providing the barest of minimums to "deserving" people. Theda Skocpol has a book about the American Welfare system that argues it was created to help widows and orphans, and only gradually expanded to other "deservings" (like veterans). In this system, “limits of welfare equal the marginal propensity to opt for welfare instead of work. Entitlement rules are therefor strict and often associated with stigma; benefits are typically modest.”

What Esping-Anderson calls the social democratic system, on the hand, had a very different idea. They provide for everyone. The famous baby boxes that all Finnish mothers get, regardless of income, is a great example of this social logic. Epping-Anderson writes "“all strata are incorporated under one universal insurance system, yet benefits are graduated according to accustomed earnings. This model crowds out the market" [i.e there aren't private retirement options or private health care options in the same way]. “The ideal is not to maximise dependence on the family, but capacities for individual independence.” The state “takes direct responsibility of caring for children, the aged and the helpless.” It is committed to “allow women to choose work rather than the household” [by providing childcare]. He has a key phrase about the goal of this system that I'm blanking on, but basically it's to provide for the needs to all its citizens.

The Conservative, mostly historically Catholic model, by the way, tends to incentive motherhood and provide services only when family resources are exhausted. It's built around assumptions of strong families. Turkey's welfare model is like this, and you can see it everywhere. For instance, in a hospital, there's an assumption that you have a family care-giver with you. You're expected to bring your own food, for the most part, and have someone who can, for instance, bring your blood tests down the hall for you (rather than a doctor, nurse, or lab tech in other systems).

The Swedish model, by the way, did change a lot in the 1990's, though it still occupies the same relative position to the US and UK, and still employs a different social logic. But that's the real point of Esping-Anderson's argument: that there are different social logics at play. In the 1980's, one can argue, that the UK and the USA got more extremely liberal in the goals of their social policy, and in the 1990's the Swedes stepped back their strong state goals slightly. But the era had different effects because they were already on such different trajectories. Esping-Anderson will be the first to say that his model is about ideal types, rather than perfect categories, and no system is "purely" one logic or another. You can also find numerous articles criticizing this system, and arguing that there are four worlds, or that the three worlds no longer exist, or that they never existed, or whatever. You know, what you expect from a book that has been cited thousands and thousands of times and is the basis for an entire academic subfield.

A key strength is indeed often seen as the Scandinavian system's universalist approach, in which welfare should be financed by all (ideally through general taxation rather than individual insurance) and available to all regardless of class. Where British and German programmes were initially aimed at urban workers, Scandinavian labour movements weren't strong enough to push through preferential treatment or to inspire it as a counter to working-class militancy, while agrarian interests were able to insist on universal contributions or entitlements, whether to relieve Danish farmers of local poor rates or to extend provision to Swedish agricultural labourers and smallholders. Partly by the accident of the balance of social forces from the 1890s to the 1930s, Scandinavia arrived at an inclusive, broad-based system later echoed in Britain's National Health Service, similarly cherished by all to the extent that even welfare-cutting Conservatives have to declare it "safe in our hands". And as /u/yodatsracist also observes, Scandinavia wasn't immune from the rightward ideological shift of the 1980s, but welfare was more widely valued than in means-tested Britain where it could too readily be represented as a reward for poverty or a "benefits trap".