You're looking at income inequality, not wealth inequality. While Sweden has relatively low income inequality, it has extremely high wealth inequality.
Indeed. The low income inequality is in many ways a contributing factor to the high wealth inequality, since it is virtually impossible to become wealthy in Sweden just by working hard and earning a salary.
Virtually no 'normal' jobs have a salary much above $200k. Whereas in the US that salary is quite achievable for a lot of people by just working your way up in a normal corporation. Even CEO salaries in the biggest Swedish companies rarely break $1m and if you break $2m you have among the very highest salaries in Sweden.
https://en.wikipedia.org/wiki/List_of_sovereign_states_by_we...