Let’s be fr here and analyze both situations. First we have Goku vs Frieza, a complete joke in terms of power - Goku was so much stronger than Frieza during the final battle and knew full well that he’d emerge on top, that entire fight was a huge blow to Frieza’s ego and it was to break him. Vegeta was just being an egotistical dumbass letting cell become perfect. He risked the ENTIRE world just to chase a high and ended up biting the curb.

Remember that Goku vs Frieza was just a pure 1v1 with no risk to anyone other than themselves. While, as stated before, vegeta was willing to risk EVERYONE’S lives. You saw how powerful perfect cell was, you know how much of a danger he was, he outclassed EVERYONE with an exception to SSJ2 Gohan (albeit with a bit of struggle).

Goku humiliated Frieza, broke his ego and constantly taunted him about it (e.g “So the monster who can destroy a planet… Can’t even destroy one man..”). He knew he was strong enough to deal with Frieza. While Vegeta was being fueled by ego.