Predicted L_X,gal (Lehmer et al. 2019) versus the observed X-ray luminosity of our eRASS:4 detected sources, both in the 2−10keV range. The 1:1 relation is shown with a black solid line, while the dashed and dotted lines show the predictions increased by a factor 3 and 200, respectively. Markers containing a red circle represent new X-ray sources (see Sect. 5.3). The subset of X-ray non-detected galaxies in the same range of the detected ones are shown with gray arrows, for reference.