You need education on how powerful Goku and Vegeta became since then if that what you think.
This statement was made after BoG, after that Goku raised his power and achieved SSB, making him at least 50 times stronger.
During Universe 6 arc he trained and gained an "unknown" amount of power, while also stacking Kaio-kenx10 on the top of his SSB which made him 10 times ever stronger so that's 500x times what he was during RoF arc
After the Zamasu arc, Goku is shown to be able to fight an even stronger Hit with SSB alone so as low ball he 5000x times what he was in RoF
During the ToP arc, he uses a Kaio-kenx20 on that MUCH stronger version of SSB making him roughly 100,000x times stronger than his RoF self.
After that he unlocks UI Omen, which is AT LEAST twice that so it's 200,000x times
And after that of course he unlocks UI which is at least 2x that of Omen making him roughly 400,000x times stronger than his RoF
I won't even get into Moro arc power-ups since anime didn't adapt it.