Luca di Montezemolo visited Michael not that long ago, maybe a year or 18 months ago? He was pretty grim and made a public comment along the lines of "It's not good" when asked of Michael's condition. I'm sure some here remember that.
For whatever reason, based on doctors' input, reports from those who have seen him, etc., I have always assumed that Michael is kind of in a vegetative state.
I suspect he is conscious but more or less bed ridden and probably doesn't really know where he is. He may not really be able to speak. I suspect he can't feed himself or do anything himself.
A neuro surgeon familiar with brain trauma suggested the next time we will hear anything of substance about Michael's condition is when we will have heard he has died.
A human body doesn't last long in this type of condition.
It's a really crazy, sad situation for such a tremendous athlete and with such a legacy to find himself in. It's much like Senna; we've lost all that Schumi and Senna could have done for F1 or motorsport in their older years.
What a shame.