Without a mouse, on those PS5 locos with a notched throttle or combined throttle/brake, having a toggle to display P1 or B2 or T Off would be a great addition. Many won't use it, but i would toggle off my current speed but toggle on a notched position readout especially where B3 is followed by Emerg ! Sometimes OFF is a critical throttle position. Tx might be a shorthand ? T4 T3 T2 T1 T0 Tx Sometimes a notched combined controller has a throttle off but also a brake off just beyond it ... i listen for the telltale sound but sometimes i misjudge ... adding to that is the mild tremor in my hands that makes the PS5 controller a challenge already.
TMx for T Max ? BFS for B Full Service BHO for B handle off ? i don't have all the answers, but i know what makes PS5 harder than Steam with kybd for me.
There is a setting, can't think of the name. Whenever you move the throttle, brake, whatever, a small text will come up showing where its at.