The long, unbeaten title run was something that worked in the territory days but didn't do as well in the national days when the roster was more permanent. WWF business of the 70's was simple: bring in a heel to feed to Bruno or Backland for three months, have the bad guy rough up the champ on TV, then do the blow-off matches that The Garden, usually ending with a cage match or death match. After that the big heel either left the territory or moved down the card to do something else. And, of course, since interest in wrestling was mostly regional, most fans didn't care what The Spoiler did in Dallas once he left the Northeast.
Hogan had a lot to do with wrestling going from a monthly ritual in most cities to a quarterly or twice a year circus event. He didn't draw in the 80's if he was in an area more than twice or three times, other than the long-time WWF strongholds, although, even then, Bruno and Backlund both had longer streaks of sell-outs at the WWF's home arena.
Now, very little of this was obvious detriment to the company as PPV revenue eclipsed the revenue a big monthly house show could generate. But it did change the nature of booking and guys like Hogan and Flair never really caught on to how to keep heat for a long-term and heavily viewed feud.
I'm not a big fan of passing the title around, I guess I'm old enough to think moving it around too much devalues it but, at this point, when the company name is generally the real draw, more than any of the wrestlers or the promise of a big world title match, it does often make more sense. And I don't agree that basically 50/50 booking everything into glorified 2 out of 3 falls matches draws either. What draws is what has always drawn: building characters and stories that have an ending that people want to pay to see and then knowing when to deliver that conclusion. People didn't want to see Steve Austin lose so him passing the title around wasn't a good drawing idea, people wanted to see him win the day when they paid to see his PPV events and the company was smart to rough him up on TV but give the paying PPV audience the stunner, pin and beer celebration far more often than not. With someone like John Cena, you can probably better serve his character by booking him as an underdog and taking the title from him from time to time.
I think there's always a danger when you make wrestling too much into 'anyone can beat anyone.' Yeah, it's more 'realistic' but, in the end, I don't think that's always what people watch wrestling for. They watch it for the exaggeration and want characters to break away from the pack. Like super hero comics, reality can be a bigger burden than boon.