> Apple obviously is not working on that (fair, they have no reason to do so) and the Swift community also has no focus on Linux, since ... they are in the Apple ecosystem.

Neither of these things are true, fwiw. Strong Linux support is an explicit current goal for Swift, though it is admittedly not all the way there yet. See this post regarding Swift 6 and its goals for wider support, for example: https://forums.swift.org/t/on-the-road-to-swift-6/32862