First, some people (not all) are using other tools than Ruby. They are looking for a solution to their problems. IMHO Ruby is not even present in the discussion when people make their choices. But Rails is. So I'm not sure that modernizing Ruby is sufficient. Building a modern framework around it could be though. I mean, people go to NodeJS because of Node, not because of Javascript...
First, some people (not all) are using other tools than Ruby. They are looking for a solution to their problems. IMHO Ruby is not even present in the discussion when people make their choices. But Rails is. So I'm not sure that modernizing Ruby is sufficient. Building a modern framework around it could be though. I mean, people go to NodeJS because of Node, not because of Javascript...