Biggest company is Status and they produce excellent libraries that are very much production ready.
I agree with you problem with Nim is that it does not really shine at anything specifically. It's a research project with many different takes on how to do things. Also out of the box experience is not great. Most people do web services,crud,json and they need debguabbility. All of these are janky in Nim. There's no "best way" which everybody uses. Go has robust stdlib and backing of Google.
