See, that's why these benchmarks do no good, people jump to quick conclusions. Also i suspect that it is not properly configured in OP case ( there is a ticket submitted https://github.com/TechEmpower/FrameworkBenchmarks/issues/23...).
Also, Drupal will not use symfony2, it will use some of its components.
but
"All JavaScript configuration variables are now under_score instead of camelCase"
Is that a joke? Why did you do this? I know there are no official guideline, however most of popular js projects stick to camelCase, why wouldn't you?