Fun anecdote, but what is your larger point?

Do you think the skinheads then went on to join a moderate left party because they could actually read their party program?

At the point where you are already committed to an ideology to the point you drastically alter your appearance, you are hardly going to be deterred by a slightly harder to get book.

On the other hand, I don't see how anyone is going to turn Nazis by reading Mein Kampf. The book is hardly relevant today and a mediocre read at best, so the only ones that will make it to the end are academics, people seeking context or people that are already committed to Nazism anyway.