From 97-98, you had them pushing Austin, Rock, HHH and Kane as new, hot guys. Shamrock was new and getting pushed at that time as well. At the same time, you had Hart, Michaels, Taker and Sid hanging out at the top of the card. And, beyond that, there was an effort to get/keep a number of guys over on the midcard with varying degrees of success, but you could see the effort was there to give guys chances.
The biggest thing was that the guys on top - Hart, Michaels, Taker - were more than willing to make the new guys look like they were on their level. Sunday, the established guys didn't really do that. Bryan won against 6 guys below him on the card, Rollins left as champ but was beat by a guy who won the World title the first time 11 years ago and won the title pinning a guy who's been wrestling for 4 years who wasn't even champion, Rusev was the best built heel they've done since possibly Rock and he lost to a guy who's had the longest non-stop run on top of just about anyone in company history in a feud set up in such a way that his loss had to happen (even to those of us who hoped against hope), and Wyatt - who while not great has SOMETHING that makes him interesting - loses to a 50 year old who shows up one day a year. None of those guys - save maybe Rusev - have been given the chance to be on the level with the top guys. And those top guys are all, at best, on the downside of their peak. The time to make new guys is now, but they seem hesitant to pull the trigger.
I'll hope that Rollins gets a nice chicken heel run until at least Summerslam, but I won't hold my breath.