Just to pick on your response to 2: there’s plenty more complex interfaces than Func possible that have single-use implementations. The fact that they’re rare i

Just to pick on your response to 2: there’s plenty more complex interfaces than Func possible that have single-use implementations. The fact that they’re rare in C# is precisely because they’re too painful.to the extent that C# developers will instinctively attack the problem a different way to avoid the painful syntax.