A side effect of C universalization, especially with open source, is that people forget all about that pre-history. Hacker culture now is mostly C/Unix with a dash of Lisp and Smalltalk heritage.
But from what I remember of microcomputer culture in the early 80s, hackers in the field were doing line-numbered Basic and Assembly language - if you had exotic tastes maybe Forth or something. If you were a Basic guy C was DANGEROUS (my programming teacher spoke of C the way Nancy Reagan spoke of crack cocaine) and if you were an assembly guy C was a slow hog.
And if you had access to a "real" computer, chances are it was running PL/I, COBOL or Fortran, not C.
The 1983 video game Tron had levels named after programming languages: "BASIC", "RPG", "COBOL", "FORTRAN", "SNOBOL", "PL1", "PASCAL", "ALGOL", "ASSEMBLY", "OS" and "JCL". C apparently did not merit mention; its complete dominance didn't come until some ways into the PC era.