I think Broly did not surpass Jiren in the movie
but I think that Jiren is significantly weaker than SSB Gogeta, and that if Broly fought Jiren after the movie he would quickly surpass him. Broly's ability to catch up to people stronger than him is insane, greater than any other saiyans, and the only way to beat him is to completely overwhelm him with lethal force rather than give him time to catch up by fighting him on a level on a bit above him and only powering up further once he does catch up.
base Goget is stronger than the MUI Goku we saw in the tournament because
A) every time Goku triggers UI he gets a permanent powerup from the limit break
B) Goku only every managed to use UI while badly hurt and running on fumes If/when Goku figures out how to use MUI while at full power he'd be absurdly stronger than he was during the ToP, but for now we only have nearly dead Goku as the benchmark