Which language will survive and why ?
This question is not relevant.
Besides some occasional scripting, a developer never develops for himself/herself. As an individual, we don't _need_ software. We might fall in love with programming at some point in our life, but once we have reached a pretty good command of it, it becomes pointless.
Technology is only great when it can be used to solve complex problems, and complexity implies relationships. In other words, you only _need_ technology when you team with other people to solve problems affecting a human group (company, organization, community, etc).
The language you'll use to participate in building such a solution will be dictated by a number of criteria outside of the control of a single participant.
As an example, business continuity, time-to-market or TCO criteria will dictate choosing a popular language, so staffing the development team or training developers will not be an issue.
Here, in Luxembourg, several companies have tried and use Scala but have eventually given up because it was almost impossible to find developers already knowing it, as difficult to find trainings for developers already on the team, and Scala's learning curve was quite long. They finally preferred to migrate to Java 8, which addressed the points that had motivated their previous adoption of Scala.
These considerations apply not only to programming languages, but also to frameworks, libraries and tools, of course.