And Swift 6 will likely see Swift on Windows, sometime next year. That work will be built upon the efforts for Swift on Linux, so you can get ready for that today.
As things currently are you are better off with C++ on the server than with Swift. This is how bad things in reality are.
I could imagine a micro-service here or there where Swift is involved in some kind of bigger enterprise architecture, or as a hobby project, but the ecosystem, the libraries, the documentation, and the community just aren’t there yet.
It’s pretty easy to take Apple’s HTTP implementation, add a router, integrate a template engine and have something running, but I don’t see a reason for this in a professional environment, and I still don’t see Apple as the company who will push a technology that isn’t directly bound to their hardware.