Upper panel: Local black hole mass-stellar mass relation predicted by DECODE colour-coded with the L_bol/L_Edd ratio. The red solid and dashed lines depict the mean relations from DECODE for the black hole quenching (this work) and halo quenching (F25) scenarios, respectively. The red dash-dotted line show the case of adopting the JWST Pacucci et al. (2023)M_BH − M_★ seeding. DECODE’s results are compared to the observationally measured relations from Kormendy & Ho (2013, blue dotted line), Reines & Volonteri (2015, orange dash-dotted line), Shankar et al. (2016, green solid line and shaded area) and Baron & Ménard (2019, purple dashed line). Lower panel: Same as upper panel, but colour-coded with the galaxy specific star formation rate. The blue and red dashed lines show the average mass evolution of black holes selected in star-forming galaxies with stellar mass 10¹¹ M_⊙ < M_★ < 10^11.2 M_⊙ and quenched galaxies with stellar mass M_★ > 10^11.5 M_⊙, respectively, approaching the mean relation from below. The blue and red dotted lines show the same quantity but for black holes approaching the mean relation from above.