rules do make a difference. i would always get so frustrated with Pride when someone would be mounted or in side control and get half way through the ropes. the guy who worked to gain the dominant control would then have to fight around the ropes etc. also, no elbows on the ground and allowing head kicks to downed opponents gave a huge advantage to strikers IMO. I also get frustrated when a sub is about to happen and the horn sounds... back to standup for the next round. Just recently with Max Holloway and Pat Schilling that happened. Schililng pulled off a pretty dangerous looking knee bar at the end of the round. IMO if he had more time chances were high he would have tapped/damaged Holloway. He got absolutely manhandled on the feet for all the 15 min, but his BJJ moment could have ended the night under the old rules.
Lets be honest, though its' not a fight it's a business. I don't think anyone who is not a gracie wants to go back to shamrock/gracie type fights that last foreever and nothing really happens or wasn't it shamrock/severn that danced around and slapped at each other forever. (Shamrock has been involved in most of the worst fights in UFC history). Those fights were more "real." The Gracie's can keep doing that behind the scenes in their gym under their Vale Tudo if they want it just won't make any money.