Yes, but even though there were some advanced compilers back then, particularly for Fortran, there were also really dumb compilers for C and Pascal in the 1980s

Yes, but even though there were some advanced compilers back then, particularly for Fortran, there were also really dumb compilers for C and Pascal in the 1980s that didn't do any of that, and just did local register allocation statement by statement (storing to the stack after every statement), which is probably more like what they were used to.