Swift was designed to seamlessly blend functional and OO styles from the get go.
Fundamentally, there's still classes and inheritance everywhere in C#, which is also what I hated about Cocoa and using it from Swift before they came out with SwiftUI.
Now don't get me wrong, I am not saying C# is a bad language, just that when you compare it with Swift, Kotlin, Rust etc, it's clearly playing catchup.
> far bigger lib ecosystem which is the most important criterion
Going by that metric, you could argue there's no point to C#, because Java likely still wins handsomely on that front and maybe Java should just give it up to JavaScript anyway.
Clearly we don't just evaluate languages solely by the size of their ecosystem. There's a critical mass that needs to be achieved, but at some point there's 2-3 libs for everything you may want to do and simly having 5 more is not magically better, the same way having "millions of apps" on the App Store doesn't mean much if most of them are not that great and people stick to just a few.
As an example, the GUI situation on Windows clearly offers more choice for C# devs as to how they want to go about their GUI, but I'd argue the Windows GUI situation is a bit of a hot mess right now and SwiftUI seems like a breath of fresh air compared to that.
