With effort Electron apps can make use of Node native modules and do just about anything you want them to do.
In the peculiar Windows case, you can share much of your JS code with a "proper" UWP app as JS is a supported platform choice. With a bit of shim work you could even support almost all of the Electron API directly on top of the UWP.
I imagine that supporting AppleScript, etc, is a lot more common amongst developers that focus on MacOS vs developers that develop an application for three platforms.
As with any application platform, in some cases developers benefit from community effort and (ahem) platform effects: if, for example, a Mac OS developer really cares about AppleScript and builds a very good, simple way to provide it from an Electron application other developers might just do it because it is easy low hanging fruit to make Mac users happy. Theoretically it's even the case that if such a thing were used enough it might get baked into the Electron platform itself making it even easier to support.
Certainly if you can find a way to make it apply to multiple platforms (ie, "oh and this AppleScript tooling is similar for what we might want for IFTT support and these IoT platforms too"), then it has more value to a developer to support and makes it more likely that a developer will support it. (One example in Electron today is that most platforms have a concept of indicating progress status in their launchers/docks/taskbars, so Electron makes it easy to support all of the variations of that.) The complaint can be that in trying to build multi-platform supporting code is sometimes you get a "lowest common denominator" approach, but that leads us back to the original question that I answered which is that Electron certainly gives you the opportunity for developers to do the more specific things when they want to and isn't necessarily locked into "lowest common denominator".
From a general power user perspective: a cross-platform toolkit makes it more likely I see the application at all on my chosen platform; whatever the developers add to make it feel more comfortable to work with on my platform is a bonus.
In the peculiar Windows case, you can share much of your JS code with a "proper" UWP app as JS is a supported platform choice. With a bit of shim work you could even support almost all of the Electron API directly on top of the UWP.