We've been running Rails apps in production continuously since 2007. If you treat software as anything other than completely disposable, it's been a no-brainer for the entire 19+ years I've been paying attention (not despite its age, but because of it). The premise that you get meaningful efficiencies from JavaScript on the back-end just because you have to use it on the front-end has been pretty thoroughly debunked…
In late 2025 we decided to migrate one of them to Inertia. Public facing pages is already done, and we're 80% through migrating the logged in area (it's a huge app). We choose Vue.js.
It's amazing how powerful this stack is and how little you have to change in the backend.