Many of the problems of AppleScript come from inconsistent scripting support from the applications. A command in one application will work subtly different in another one. Unfortunately, this problem will continue with Javascript.
Back in the OS 9 days, there was support for additional languages instead of AppleScript. I recall that someone did a Perl implementation and I think there was a later Javascript implementation. This support was pulled at some point in the OS X days. I'm glad to see that at least Javascript has been added back.
> This support was pulled at some point in the OS X days.
The underlying tech ("open scripting architecture") has been there all along though, so third parties could have implemented OSX bridges regardless of what Apple shipped. I can only assume nobody really cared much, leading apple to remove alternative implementations and nobody to take up the slack (because nobody really cared much)
ScriptingBridge which was a layer to formally connect other languages to OSA is still there (unsure about 10.10), but neglected. It was introduced in 10.5 along with official support for PyObjC and RubyCocoa in that release. Apple also touted being able to do the same from Objective-C.
Other 3rd party language bridges such as LuaCocoa and JSCocoa provided ScriptingBridge support.
Back in the OS 9 days, there was support for additional languages instead of AppleScript. I recall that someone did a Perl implementation and I think there was a later Javascript implementation. This support was pulled at some point in the OS X days. I'm glad to see that at least Javascript has been added back.