runtime have versions too. If one runtime version use only one flatpack than exactly same as just static linking binary. Flatpack have just docker layeredfs and firejail in base.
id: org.gnome.Dictionary runtime: org.gnome.Platform runtime-version: '45' <- here sdk: org.gnome.Sdk command: gnome-dictionary
In the initial stage of shared library support, everything was exactly the same. Let’s look at it in 5 years… When some soft will archived and die, some stop maintaining, some new crated and brakes old dependencies…