On my Thinkpad 2in1, the behavior your desire is what I get. I'm on Fedora KDE (Kinoite) which pre-installs Maliit by default though, I'm not sure if it comes with some additional configuration.
The help page of virtual keyboards mentions detecting a hardware keyboard, but that’s all I know. Does it not detect the keyboard built into my laptop? It makes no sense to me lol.