I’m not sure I understand your argument here @mdedetrich. Nobody in the thread previously has mentioned using String as the error type for Either and the rest of your post implies that the best strategy you found was to use Either with a sealed trait of error values, which is exactly how Either is used by the rest of the community now.
As far as I can tell the problem with Try are far more significant than the problems with Either for functional error handling and it would break tons of existing code to change Try to be suitable.