> Seems like most of the Ruby gains are related to memory usage.

That would be a welcome addition, especially with Rails where you typically end up running your web app, background worker and action cable as separate processes. That's (3) running services each booting up your application to some degree.

Combine that with most apps using very little CPU and more and more memory, it's nice to be able to reduce memory when you can to optimize the machines you host things on. It always feels dirty having a server using 60% memory and 5% CPU.