That is correct, I did not mention Linpack. It had different function names than Lapack though (while the naming scheme was similar, and still constrained to 6 letters); for instance DGETRF was named DGEFA in Linpack. [1]
Yes. Lapack was the successor to linpack and I seem to recall some of the linpack routines going back much further than the eighties. MATLAB (which existed before the commercial release in 1984) was built on linpack.
[1]: https://netlib.org/linpack/dgefa.f