Sweden has more billionaires per capita than the US. It's a largely free market economy, so is France. Government does have more of a role in private enterprise there than here, usually, but we have things like the TVA which is similar.
They aren't "socialist" economies. The main party name is "Social Democrats", not "Democratic Socialists". They have very high taxes on the middle class, they are crazy high relative to here, to pay for a lot of social benefits like health care. That isn't socialism.