Total flux ratio between substructured and compact disks at different wavelengths. The average dust-integrated flux at the same distance of compact disks from 1.3-mm, 3-mm, 1-cm, and 2-cm fluxes is confronted with that of substructured disks. Fluxes at 7 mm are not shown, because the subsamples are too small. The red points indicate the fluxes integrated over the inner 40 au from the ALMA highly resolved images. At 1.3 mm, the compact disks have relatively lower fluxes than at the other wavelengths, while a similar value (50%–60%) is found when considering only the inner 40 au, suggesting that the emission from this disk region is severely optically thick.