what does `systemctl --user status app-steam@autostart.service` say?
what does
systemctl --user status app-steam@autostart.service say?systemctl --user status app-steam@autostart.servicecp /usr/share/applications/steam.desktop ~/.config/autostart/steam.desktopmarked by itself 
cp /usr/share/applications/steam.desktop ~/.config/autostart/steam.desktop