Except e.g. React and Express are so different and work on such vastly different domains that them being in technically a similar VM is more or less inconsequen

Except e.g. React and Express are so different and work on such vastly different domains that them being in technically a similar VM is more or less inconsequential. They're two entirely different disciplines and have different build pipelines, deploy pipelines, etc. I don't see much benefit in having them in the same language. One thing does DOM state while the other does ~play in traffic with libuv. Like hey it's nice that this OS kernel is implemented in C, good thing I am also writing my GUI in C. Idk, maybe it's a boon for some, but I've tried it and don't really see the big appeal...except for Meteor, because if I'm writing both my UI and API in the same * language, why in the would I need to write my models in both places and maintain them separately. But meteor has problems too, I just always thought it was neat way of doing something that would only be possible ("easily") when using the same lang on both sides.