Go's development is tied to Google Inc. and is widely used at Google. Same with Microsoft's C# with .NET and Swift isn't very different to this as long as it is open source.
So this really is a moot point.
Additionally Google isn't selling Go as a product in the same way as Apple does Swift (and where Google does publish public Go APIs it also tends to use them in the same way as their users do, so the interests are more aligned)...
Hmm, Apple isn't selling Swift as a product either; it's literally what they needed for their own platform, much like how GOOG needed Go for their server works.
I'm less concerned about go, because unlike swift and c# it was designed from the beginning to be cross-platform and if anything Linux is the best supported OS. But barely so. Also, if Google were to discontinue support, or change the license, or do something else disruptive, I have more faith that the ecosystem would create a fork to continue the language.
FWIW, my biggest concern isn't that the language would be completely abandoned, it is that the company would diminish or drop support for tooling on OSes and editors and IDEs that compete with the company's products (Mac OS and Xcode for apple, Windows and Visual Studio for MS).
That said, F# was years ahead of C# in features C# is still chasing, and is driven mostly by the open source community. That community is more in academic and finance areas where Linux-first is common. The language is standardized and plugged into VM improvements over time.
Frankly, I see the lesser degree of entanglement with MS corporate interests as a boon for the language and its ecosystems long-term utility.
The problem is that it's closed source, and its license specifically prohibits its use with anything other than VSCode. Unfortunately, this is becoming the usual modus operandi for first-party Microsoft extensions for VSCode for all the talk about how they "love open source".
No it wasn’t. There were so many foot guns for windows and in fact to this day you cant use CGO with MSVC (insane to me).
I can’t even say with a straight face today that Windows is the best supported OS for C#, because it’s not true