I am not sure what exactly is lost? The mechanical things are still there, and it is even easier to make them. Unfortunately, it turns out that they are expens

I am not sure what exactly is lost? The mechanical things are still there, and it is even easier to make them. Unfortunately, it turns out that they are expensive, so they have been relegated to either very expensive devices or to beginner's devices. Take a look at high-end scope or ultrasound machine control panel -- they are full of beautifully designed knobs and switches. And on the opposite end of spectrum, if you look at instructables/hackaday, there are tons of project to interface anything mechanical. Same goes for the discrete circuity. Get one of those cheap plastic solar lights -- you may find there is no controller in sight, just a bunch of old-style transistors. And on the other side, no SOC will have a 1GHz AFE or 20 amp output.