According to a press release that was just recently sent out, Drag Mode was apparently absent from the Need for Speed franchise for six years. However, that all changed when the mode was re-introduced in the free-to-play title of the series, Need for Speed World.
These changes seem to be a good thing because now the number of registered users is over 20 million. For any title, especially a free-to-play one, that is a huge milestone.
Source: Press release