Ideally there needs to be a TVM which a wheelchair user can use at any station with TVMs but that doesn't mean every station needs the pin pad at a position where it can be operated by someone sat down. One good thing about the new Northern TVMs is apparently where the meaningful part of the display is on the big screen changes according to the height of the person using it.
Yes, that's quite good. The issue with the low PIN pad is that it's inset into the machine so I can't see it from full height. If it was flush with the face of the machine it would be possible to use it from any height. I do indeed like the feature of the "big screen" machines that the TVM display can be at any height you wish, though using one lower down is fine provided I can see it (and it's angled upwards)!
Train open-door buttons on the inside are getting similar - the "open" button on most newer stock is at the lowest point it can be without me bending my knees or back to reach it. I think the long-term solution to this one will need simply to be two sets of buttons, one set low down, one higher up. Providing two PIN pads, one about 0.7m from the floor and one about 1.5m from the floor, may also be a viable option.
It's not a problem now, just irritating, but given that I already have mild knee issues by the time I'm say 70 it may well be. And while people do shrink a bit in old age, when my generation (and the even taller younger one) make it to old age it will be a wider one.
FWIW, many banks now provide two ATMs, one at wheelchair height and one at non-disabled adult height.