We previously had Calibri for Windows (indeed a very popular Windows system font). Gill Sans (which we now ship to all operating systems) is a quite popular MacOS and iOS system font. I currently think there are some weird rendering issues on Windows, but if that’s fixed, my guess is you would get used to it quickly enough. Gill Sans is not a rare font on the internet.
We previously had Calibri for Windows (indeed a very popular Windows system font). Gill Sans (which we now ship to all operating systems) is a quite popular MacOS and iOS system font. I currently think there are some weird rendering issues on Windows, but if that’s fixed, my guess is you would get used to it quickly enough. Gill Sans is not a rare font on the internet.