neoliberalism is a function of capitalism's contradiction of requiring constant exponential growth. in an infinite timeline neoliberalism will sadly completely consume any semblance of "social democracy", and you can already see even the classic european social democracies are beginning to eat away at and privatize their welfare states.

other people are also pointing out unequal exchange, which is a critical concept to factor into the equation when trying to understand where the wealth of the european social democracies come from.

https://www.youtube.com/watch?v=rjLmYCfKU7o this video is a really good short primer on the topic!