Kahoot's Answer Streak Bonus is No More.
Around August 1st, Kahoot Krew member, Bryan, released an official statement stating the removal of bonuses.
As of today, bonuses are officially a thing of the past. Answer Streaks still exist, but there are no points awarded for them.
Apparently, the removal of this feature was planned a few months ago in this post.
Answer streaks are still in the game, but the points have been removed. As said by Bryan, answer streaks keep the game fun and competitive without affecting the underperforming students who fall to the bottom when losing their streak. Most of the community agrees that it was not a good feature for most purposes, as it wasn't quite fair: imagine a student who failes at the 4th questions and well defeated by another one who failed at the 1st question [sic] (IEM_2016)
While it is a little disappointing that Kahoot! didn't simply set the feature to be disabled by default and add the ability to turn it back on, they at least left the code for the answer streak points in. (However, it is hardcoded to be disabled)
How to re-enable Answer Streak Points
To get answer streak points back into your game, install Kahoot AntiBot. Kahoot AntiBot has many features, including enabling Answer Streak Points.