No one cares how the sausage is made. They care that they have sausage. I write code to make money, not for uptime competitions. If something that makes money needs to be restarted every 4 minutes and customers are willing to pay for it why should I give a shit?
FCGI problems were very customer-visible. Prior to Zed coming along, the issue wasn't being discussed much anywhere, making it unclear if it was your code, ruby issue, framework issue, or appserver. Now it is your problem to fix!