Dates given by who and backed up with what facts? The is a ton of manure spread on Macrumors every day. It is just plain junk. They no more define reality than folks who claim the world is flat. It isn't.
Who said they were based on facts? The problem is
no one has any facts because Apple hasn't seen fit to provide any form of guidance.
Having said that I think you misunderstand what those lines in the sand were. It goes something like this:
May 2016:
Q: I want to buy a Mac Pro but the current offering is dated and not even discounted. Should I buy or wait until Apple releases a new version?
A: No one knows when (or if) Apple will release a new Mac Pro. However WWDC is right around the corner so I would wait until after that to see if there's an announcement.
July 2016 (with no announcement of a new Mac Pro at WWDC):
Q: I want to buy a Mac Pro but the current offering is dated and not even discounted. Should I buy or wait until Apple releases a new version?
A: No one knows when (or if) Apple will release a new Mac Pro. However the new iPhone launch is right around the corner so I would wait until after that to see if there's an announcement.
September 2016 (with no announcement of a new Mac Pro at the iPhone launch):
Q: I want to buy a Mac Pro but the current offering is dated and not even discounted. Should I buy or wait until Apple releases a new version?
A: No one knows when (or if) Apple will release a new Mac Pro. However October is right around the corner so I would wait until after that to see if there's an announcement.
At one point in time, there was much better signal to noise ratio on Macrumors. Sadly it appears there is an increasing number of newcomers who think dispensing made up stories they pull out of their butt is normal and the primary purpose of these forums. It really isn't. This is not intended to be a fiction writers forum for new stories. Just because people resubmit their fiction stories 10-15 times over a couple of months doesn't turn them in factual documentaries.
The difference is at no point in Apple's past have they had a "No buy" recommendation for
all of the Macintosh products. People are, rightly so, concerned about Apple's commitment to the platform. It's not just M.R. where this is happening. It's happening all over the web.