Tadej Pogacar breaks 3 Strava records during his reconnaissance for Paris-Roubaix 2025 including fastest time on Mons-en-Pévèle

Being a heavier rider means you have more momentum entering a cobble sector, as your wheel hits every cobble you are going through them at a higher momentum than a heavier rider, so the lighter rider needs to pedal faster to overcome the cobble, furthermore as specified above you have to also consider the fact that the rolling resistance will affect riders of different weights, tire pressure, techniques.. There is also the fact that a heavier rider has more absolute power.
TT riders tend to be good when they are of a higher weight. Explain then why are Ganna, Van aert, Kung, Tarling, etc, favorites on flat ITT? Pogacar has lost several flat TTs to heavier riders..