Nope, you are just generalizing your opinion which is not quite true. My (and my colleagues) experience studying/programming C/C++ from the beginning-90's has been pretty good.

When the PC explosion happened, a lot of programmers without any CS background started with C programming and hence of course there is a lot of code (usually not long lasting) which do not adhere to software engineering principles. But quite a lot more C code was written in a pretty good style which was what one picked up at work if not already exposed to them during studies.

I still remember the books from late-80's/early-90's on the PC side, by authors like Al Stevens (utils/guis/apps using Turbo C) who wrote for Dr. Dobb's Journal. On the Unix side, of course you had Richard Stevens, P.J.Plauger, Thomas Plum etc. They all taught good C programming principles which are still relevant and practiced today.