The myth of Dracula comes from the fact that the writers of German origin did not like this man. It is true that he did a lot of killing, and he destroyed many lives. It is true that his power came form the fact that he learned his techniques of torture during his years as a vassal under the Ottoman Turks.
The problem lies with the fact that he was cruel to one community which sent letters of said cruelty to them to Germany. This is where most of the Western European historian take their information from.
Vlad Tepes was an erstwhile ally, the same can be said with his father.
Still, Dracula, the myth, the character, comes from these writings. Stoker would have not had a character to write about had he not had access to a western based book, and Dracula, would never have been created. This creation has lead to tourism for Transylvania, and more money for the area.
So Vlad Tepes was important in terms of money later on, but it took writings from a darker, more negative point of view to do this.