It might also be an issue with motivation. Would you want to work on something that's basically a clone, so there's no creativity but purely porting + solving annoying platform-related bugs? You'd probably tolerate it for a bit, but then it's just playing catch up all the time. It seems like a recipe for employees trying to switch away to another team or company.
They did it for control and convenience at the expense of literate computer users.
The Windows 10 UI is written in TypeScript, Edge is chrome, Chrome is chrome, Safari is chrome - it makes hiring and training easy when you can just make every API a grey gelatinous chunk of ECMA script with hamburger menus. It also means the "app" is always sandboxed unable to do powerful things like universal push-to-talk.
The color and joy of using programs has been flattened out in the name of consistency.
https://medium.com/commitlog/electron-is-cancer-b066108e6c32