Well, 2. is what the people are asking for but aren't getting. They want deprecation and a ENV flag to enable. It'd be enough. But even that isn't being allowed which is weird for a power-user program. I can't help but think, "Don't obey in advance."
They're deprecating it and removing it. What is required is deprecating it and leaving it in (with env flag to enable) till it actually breaks rather than obeying in advance.
