Supermassive black holes (SMBHs) are likely ubiquitous in galaxies, but the driving mechanisms that trigger them as Active Galactic Nuclei (AGN) are still poorly understood, due to short-time variability, galaxy contamination and other selection biases. Deep multi-wavelength galaxy surveys in the last decade have been truly unlocking this field of research, steering AGN-oriented studies from the black hole to the galaxy's perspective. In particular, X-ray and radio observations of mass-selected galaxies have started to constrain the "typical" radiative (X-ray) and kinetic (radio) AGN power across the galaxy population. Our studies suggest that AGN activity evolves super-linearly with galaxy stellar mass since the "cosmic noon". An intriguing implication of these findings is that SMBHs and galaxies did not build up their mass in lockstep, at odds with the common idea of coeval growth.