We need new languages and ideas to keep developing, obviously if someone is willing to put a lots of time and effort they found existing ones lack in something. Even if the difference is only 20%.

Talking specifically about Go, how much time did it take for Go team to acknowledge and make some workarounds to support generics? And this is not a new concept it exists for more than 30 years. I can not imaging Go actually developing and incorporating new things, it is a simple and "completed" language.