Here's what I think.
People haven't "suddenly" decided he is no good. Nor is he "boss".
Over the course of the season just gone people have gradually come to the realisation that John is not as good as many of us thought he was this time last year.
That is not his fault.....ridiculous levels of hyperbole were heaped upon the lid on foot of one full season playing regularly as a centre back in the EPL.
A totally absurd amount of money was offered for him by Chelsea and this enhanced his reputation among Evertonians, myself included, whom bought into the hype for a time.
Now we are seeing John for what he is.
A youngish centre back with great potential, still learning the trade and who may or may not mature into a great centre back.
Only time will tell.
FWIW I think John Stones would be best suited by staying at Everton and letting one of the best centre backs we have ever seen take him under his wing and whom might help him realise that potential.
(assuming Ronald is coming to us, that is.......Blimey O'Riley, this wait is getting old now :()
If there was one thing we learned about John this past twelve months it is that he found it hard living up to the expectation and the hype hence him being taken out the firing line in the middle of the season when his limitations were being exposed on a regular basis. He came back all the stronger for that, but he still has a bit to do to start living up to the hype.
And this pressure will be ratcheted up many fold if he goes to City or Chelsea for a massive fee and fails to set the place alight immediately.
As ever, all IMO :)