This is a rather small userbase when it comes to enterprise.
Especially because Swift will never be as versatile as Python or as efficient as Rust.
And then there's also Go, C# and Kotlin with much better tooling.
Me not liking something, does not make it bad. It’s just not my choice. I’m glad it existed, because it probably prompted Apple to do better with Xcode. Lots of people that I respect, used it.
These days, Xcode is Big Bug Ranch. When “Delete the DerivedData folder” is S. O. P. for developers, and Apple tweaked Xcode to reduce its impact on the project, you know that they have waved a white flag to bugs.
That's the same dynamic as web devs writing React Native apps: you won't expect them to contribute extensions that manipulate local apfs metadata for instance.
So while it's nice to have them use the tools, you still need people who primarily care for non Apple platform and embrance swift for their purpose to have it expand.
This might work the other way round: starting from people familiar with macos or ios development who want to write for other platforms.
Then the question becomes: why would a developer learn a different open source language when they can use what they already know. And sure, depending on the context they might still go with Python/Kotlin/Rust/etc.