>What will probably is that MS will make optimizations for VS Code to run even better and then make those optimizations open for everyone.
They already could of with the MIT licensed Electron... Literally nothing stopped them from doing this prior, unless the project as said has a bad structure but I find it hard to believe.
Having control of the copyright gives you control of the development process as well. So getting 1000 patches into a project just becomes a whole lot easier if you own the copyright.
It's as if everyone hates Microsoft enough to believe they have different rights under the MIT license. MIT is as permissive as it gets, if Microsoft wanted to they could of released VS Code as a close sourced but free (as in money) product, and NOBODY not even GitHub would of been able to stop them either!