Why do you think that though? It makes a lot more sense to me contextually (and knowing that Gaban appears to be globally less infamous) to take the statement as being in reference to power level
Because they said he's a legendary figure equal to Roger and Rayleigh.
He didn't say he's equal to Roger in strength. He kept the statement vague.
Thus, I assume that strength is only one component of that comparison. You have to be exceptionally strong to be legendary. But it is their legends that are comparable, noted by the story said about how he became known as the mountain eater. Basically, he's that guy.
Garp made a similar statement about Whitebeard and Rayleigh both being legends without any distinction of them being different levels of legendary. Doesn't change the fact that Whitebeard is stronger.
This is just a forum where the most powerscaling obsessed readers congregate, so it's no surprise that there is absolutely 0 nuance to their understanding and they only see statements like this as mere ruler measurements of combat strength.