Let's be clear - Apple put their users in harms way by letting a bug of this nature slip past testing. Disclosing "responsibly" would certainly be nicer to users, but mostly it would be nice for Apple by helping mitigate the bad publicity.
Fixed that for you.
Sorry, I'm not going to cater to the lowest common denominator of "users". If my system has a hole, I want to know so I can get in a fix or shut down that particular feature until its fixed by a vendor.
Ive only 60k machines and 40 clients that depend on that decision. And they agree with me. If something's broke, I can analyse how it breaks and if it impacts us. If it does, we can triage it. I can do a damage assessment. I certainly can't do that if it's being sold on the darknets and whispered.
That assumes you can shut down that particular feature without crippling your business operations. If my system had a hole, I'd prefer that it were disclosed to the vendor before it's disclosed to hackers, adversaries and foreign governments.
I've seen the dark side where this leads. It leads to BTC transactions and 0days bought and sold. That's the worst, further past scrappy company sitting on exploits.
I strongly believe in transparency. It empowers users and admins more than any other option out there.
Disclosing this immediately puts those people who can't setup enable the root and set its password into more harm's way.