I just tried that in 3 different applications: Finder (search bar), Notes, and Slack (just in case it was an Electron specific behaviour). I couldn't get those readline/emacs bindings to work on either. This is a brand new MacBook Pro with all the defaults for the UK region so it's definitely not something I've (knowingly) disabled.
Is this something that needs to be enabled? Or is it dependant on something else to work? It's definitely a feature I'd welcome.