Left panel: comparison of the distribution of the mass ratio q when we use the posterior distribution marginalized over the chirp mass (green) or the posterior distribution conditional on a given chirp mass (blue). Both distributions are very similar, which is why we argue that the usage of the marginalized distribution throughout the Letter is justified. Right panel: prior distribution on the mass ratio q in the black dashed lines, the posterior distribution on q in green, and the reweighted posterior that corresponds to a flat prior in q in blue. Note that the prior distribution on q is only for a small interval in chirp mass where there is posterior support, which is why there is more support toward lower- than higher-mass ratios. We conclude that there is slightly more posterior support for equal mass ratios when reweighting but this is negligible compared to the statistical uncertainty in GW170817.