This seems a little headcanony. We don't have a standard for what timeframes of encounters count towards determining whether a statement stemming from that encounter is valid or not.
The point is that Genos has seen Saitama dispose of the meteor easily and by himself yet with Gouketsu Genos thought it would be best if Saitama had support from S-Class heroes. If there was another meteor identical to the one Saitama destroyed, Genos wouldn't have said what he did about Gouketsu as he knows Saitama could easily handle it himself.
I don't see how this demand to be spoonfed something really specific debunks Genos' statement about Gouketsu.
Gouketsu is a short-lived character. He was there to cause some troble and be one punched by Saitama. Yet it's clear that ONE and Murata intended him to be powerful beyond just his feats considering the lengths they went to have many different characters say he's a big deal.
- Genos' statement about him.
- Suiryu saying he was on a whole other level than Bakuzan (a Dragon level monster)
- Gyoro Gyoro saying that many S-Class heroes would be too much for even Gouketsu to handle.
- Gyoro Gyoro being really surprised by Gouketsu being defeated and not being able to think of who could've done this despite having a lot of info on the S-Class.
- Hellfire and Gale stating that the power gap left by Gouketsu and EC was too big to be filled by the inclusion of Garou into the MA.
- Gyoro Gyoro assuming that the Hero Association have some secret weapon in their arsenal due to Gouketsu dying (as in the eyes of the HA and MA King defeated EC so GG wouldn't consider EC's defeat as due to this "secret weapon"). Gyoro Gyoro even says that this secret weapon may be above the S-Class.