Trend of simulated rms of the residual Faraday RM, observed at z = 0 and for integrating out to increasingly larger redshift (up to z = 2.5), for our A3, B4, and C1 runs. The lines give the mean dispersion of the RRM_f for 100 randomly selected lines of sight through the simulated volume, while the black line with larger error bars shows the observed RRM trend by LOFAR, taken from Carretti et al. (2024).