That's true, the major design of Soyuz (structual composition, 'appearance' of the ship) was developed in USSR, and maybe in 10-15 years it will be completely obsolete. That's why our space agency develops new one to replace Soyuz. But do you really think it is the same ship that was docking with Apollo in 1975? Computers, engines, construction materials, docking systems, even parachute - the ship had been constantly improved, and I can assure you, it's not the electronic tubes and perforated tapes that run the ship's computer
Regarding touchscreens, it seems the central screen on a photo is a pretty much digital display. But I guess, the main systems are controlled by push-buttons instead of touchscreens because they're more reliable and easier to use when you are in spacesuite. If you take a closer look, you can also see that some of the buttons are partitioned (not sure if word is correct) to avoid inputing wrong commands into the computer while ascent/descent, when the ship is shaking.