Wrong. Transistors have evolved in dozens of directions. The old transistors are still used, but decreasingly so. It is likely an op amp does better what your transistor and a bunch of other stuff did, and equally as cheaply. The op amp might have bipolar transistors in, but just as likely not.

C has not evolved because C++ has, and because the computers got a million times faster, so even Python is usually good enough. If you need something that does what C does, but better, C++ is right there waiting. Change your makefile, or rename some files, and suddenly you have a C++ program, that is then easy to improve as much as you like.