Running with the dotnet executable works, debugging in vscode does not. It's readily reproducible and likely an effect from an obscure and common issue. (Maybe the "proprietary" nonsense) I could dig in and waste my time on the issue tracker, but I'm not the mega corp with a money printer.

Microsoft has many low quality teams, especially in some of their dev tooling. The natural consequence is that it's primarily tested on Windows, and has evolved many failure edge cases on other platforms.

The proper conclusion is - c# is for windows, just how it's always been. Using it is selling the business's products to Microsoft and forever ties it to their endless tech debt.