You can use newer LangVersions with older targets, including .NET Framework. A good deal of features can be made work by just setting LangVersion: 13 and doing

You can use newer LangVersions with older targets, including .NET Framework. A good deal of features can be made work by just setting LangVersion: 13 and doing dotnet add package PolySharp. But of course this won't bring missing span-based APIs, new ASP.NET Core and EF Core, etc. However, the workplaces that adamantly refuse to upgrade also select for developers who may not be familiar with pattern matching or other features at all, and never read release notes.