> Not to mention that porting WinForms from .NET Framework to .NET 6 requires a rewrite for anything more complex than a Hello World. We sell a fairly complex

> Not to mention that porting WinForms from .NET Framework to .NET 6 requires a rewrite for anything more complex than a Hello World. We sell a fairly complex custom control, both for Windows Forms and WPF. There were zero changes necessary for the migration to .NET Core 3 back then. We still build both .NET Framework and .NET Core assemblies from exactly the same source. Depending on how many 3rd-party dependencies are used and what other weirdnesses one does in code there may well be projects that are impossible or really hard to convert. But overall my experience was that for a lot of applications there are few, if any, changes necessary.