Linux download pages doesn't mention flatpak or load newer version
The 1.2.1 Linux download page lists an AppImage and PPA, but not flatpak, yet https://flathub.org/apps/details/org.inkscape.Inkscape is at version 1.2.1.
The 0.92.4 Linux download page does mention the flatpak, but the instructions for it say to run
flatpak install flathub org.inkscape.Inkscape
which will actually install the latest version (currently 1.2.1). According to this issue there is a way to doangrade to the flatpak of a specific (old) version of an app, I think
flatpak update --commit=1e3818e3854fef97387e9791daa67285029d2dd554d5a3bfa169cea4ef96e0d1 org.inkscape.Inkscape//stable
would install Inkscape 0.92.4, but I didn't test it. I think you have to install the latest version first then before issuing this command.
It seems worth saying somewhere that "In several Linux distributions you can install the Inkscape package and/or flatpak from the graphical 'Software Center' or 'Application Store', instead of entering commands in a terminal."