obviously, for the rivalry to be the most fun, it is nice if both teams are competitive and either team can win in any given year.
Looking at the results, it's swung from Utah-dominant, to BYU-dominant to a brief period of relative equality to Utah-dominant. It might take a few years for P5 recruiting and money to kick in, but I'd expect the two teams to be pretty evenly matched over the next 10-20 years now, which should make for a better and more enjoyable rivalry.