Imo Beerus' strength is simply not meant to be caught up to. There's been multiple times where Beerus expresses concern about getting surpassed that amount to nothing. In the movie with that retconned 70% and in the anime when he starts sweating bullets about Goku achieving Ultra Instinct. They'd gone well beyond those levels and nothing comes out of it.
Jiren is pretty powerful imo but i dont see Gogeta fusion winning over beerus anytime .
Gogeta/Vegito would trash Beerus in the manga if its powerlevels were consistent. Base Goku & Vegeta could smack fullpowered Jiren around & Jiren's specifically said to be stronger than Belmond in the manga. By extension of Jiren, Base Goku + Vegeta > Belmond, and they can widen that gap hundreds of times over with fusion alone and still have transformations to spare. It was shown that the Gods didn't really have that dramatic a difference between the each of them despite some being on the stronger side in the manga, so they should neg-diff any of the Gods.