Making JIT 4% (or whatever) faster is cool but it would probably have higher ROI for the .NET ecosystem if Microsoft assigned some of these high caliber people to instead work on improving or simply rewriting some of the atrocious open source libraries that are available.
Would you rather have an A language/runtime with a D open source ecosystem or a B for both?
Would you rather have an A language/runtime with a D open source ecosystem or a B for both?