Would you consider a feature where all controllers in an Asp.Net project are automatically subject to having their constructor generated? So like, perhaps an assembly level [assembly: PrimaryConstructor] attribute would trigger it. Or maybe simply inclusion of an Asp.Net Mvc targeted nuget package like PrimaryConstructor.Mvc could be enough.
I think the logic could be to simply look for classes inheriting from ControllerBase instead of classes decorated with [PrimaryConstructor].
If you like the idea I would be interested in taking a crack at a pull request.