Defining extremists to be "the people with unpopular positions" is defining extremists to be "those with positions most dislike." AfD are extreme because of what their positions are, separate from who does and does not support them.
a cursory Google search reveals that they deny anthropogenic climate change, reject the idea of women in the workplace, and wish to deny marriage rights to homosexuals
They are conservative and have a few idiots and extremist people in their ranks yes, but that doesn't make the party as a whole extremist.
I never heard about their women-workspace-denial.
And being against marriage of homosexuals was the majority opinion from the beginning of time until around 10 years ago so you can hardly count that as extremist.
