Observations of the growth of large-scale structure, specifically the amplitude of matter fluctuations ($\sigma_8$), indicate a potential suppression or "kink" in its evolution at late times compared to the predictions of the standard Lambda-CDM model extrapolated from the cosmic microwave background. While the CMB predicts a certain level of clumpiness ($\sigma_8 \sim 0.81$), low-redshift weak lensing and cluster count surveys often measure a lower value ($\sigma_8 \sim 0.76$), suggesting that structure formation has slowed down or been suppressed more than expected by dark energy alone. This tension hints at possible modifications to gravity, dynamic dark energy, or interactions between dark sectors (Macaulay et al. 2013; Abbott et al. 2018).