Damn, all electronics has to be digital now? And here I was working on my analog and RF circuits with a handful of transistors.
Also, while people rarely design 'digital' stuff by hand anymore (they do - high-speed stuff is still done by hand, and sometimes it's just easier to make a few flipflops by hand than to learn a digital design flow/buy the tool just to be able to set a few latches in your circuit) - someone has to come up with those gates your place-and-route tool will use. Some very common blocks of multiple gates can be done by hand as well, just to get a few ps faster propagation delay through them, which can quickly add up in a big complex chip.
People seem to often look at electronics like there are two extremes (esp when it comes to integrated circuits):
- on the one hand the full-on huge digital design, where you find people doing CPUs/GPUs/microprocessors, but also codecs and other hardware
- Or you are one of the voodoo magicians like me, spending months massaging your 20 transistors and inductors to give you just that 1 dB extra gain at 140 GHz
But there is a whole field of mixed-signal design, where you have very blury lines between digital and analog. Most would probably say digital I/O is digital - and I would probably agree with you if it is something like a 10 MHz output on an MCU. But what about a 200 MHz digital line? What about a 5 GBit/s PCIe line? What about a 112 GBit/s PAM4 output? At what point did it stop being a digital problem and start being an analog one?
Mixed signal is where the majority of interesting research and advances are being made right now. Digital design is still majorly driven by scaling - transistors get smaller and denser, how do we make better use of them for our next chip.
Analog performance in CMOS stopped really scaling around .35 or 180nm CMOS (or lower, depends where you draw the line). RF performance is optimal in CMOS around 65nm/45nm/28nm (depends on who's flavour of technology you use and what frequency you work at).