Kayfabe is something much more complicated than just a kid crying over a Cena loss because he believes wrestling is for real, or an adult believing wrestling is fake, but marking out because it is entertaining. These occurences are no different than people temporarily engrossing themselves in a TV soap for an hour, but they are NOT the meaning of Kayfabe.
Kayfabe was an all encompassing cultural phenomenon that permeated the industry and psychology of the fans. This does not exist today even on a small scale. The mentality that went into Kayfabe has been replaced by the same mentality that viewers have when watching any TV series. This is not anywhere near the same thing as Kayfabe.
Now this is completely true and sometimes when I see reviews of the original Mania cards by some IWC writers it shows their lack of knowledge of how exactly kayfabe was.
They judge WM 1-4 under the viewing habit you speak of that is used with today's product failing to understand that the product was deliberately slower with less high spots because the kayfabe was being considered.
I also think it has taken away some of the passion as well with some of the performers when selling matches.
I always show newer fans Hogan and Savage's promo against each other leading into Mania V and that was during the time period when kayfabe was broken in courts. The passion you see in Hogan and Savage you could tell they really wanted to be the top dog.
The same way some won't get why Hart and HBK were so cut throat with each other. This was not even 10 years after kayfabe broke, but the old tenets still existed somewhat compared to today that's for sure.
I actually after typing this think John Cena's way of not caring for certain things is actually why the fans of previous eras turned on him. When fans turned on guys like Hart and HBK they really took it to heart and they turned it up in their performances.