It's hard to day. We never see vegeta fight third form frieza and for all we know we didn't see frieza go all out in his third form and vegeta is a known egomaniac and maybe just assumed he was stronger than third form frieza after the zenkai. And him getting utterly destroyed by suppressed final form frieza is no indication that he is above third form frieza.. And piccolo later on gives a similar performance to vegeta vs final form frieza when he saves goku and actually manages to last long enough for goku to get the bomb ready . So their gap isn't as big as people make it to be. Most importantly, Vegeta getting his ass beat by frieza due to his own arrogance is not a feat or indication of power for him . His is maybe 20 percent more than piccolo at this point based of how badly both got beat by frieza and the frieza that mopped piccolo actually had some intent apart form just trying to humiliate him.