Yes, but for this reason, the Bluetooth implementation is on physically separate, untrusted hardware that has no access to the buttons or screen other than by communication with the secure element (see [0] for the Nano X; I’m assuming the Stax will be basically similar).

So this isn’t really different from having a USB cable: in either case, some untrusted messages arrive at the secure element over some wires, and get processed there. The only difference is that the wires come from another chip on-device rather than from an external cable.

[0]: https://www.ledger.com/ledger-nano-x-bluetooth-security-mode...