I'm not sure what you're thinking of, but there at least 3 prominent and still-relevant awk implementations:

nawk (One True Awk / AT&T awk / BWK awk): the original awk, still maintained; is used by macOS, FreeBSD, OpenBSD, and NetBSD https://github.com/onetrueawk/awk

mawk (Mike's awk): the default awk on Debian https://invisible-island.net/mawk/

gawk (GNU awk): the default awk in lots of other places https://www.gnu.org/software/gawk/

There were some differences even in the mid 90s between AT&T-style awk which was then considered the original/definitive/most-backward-compatible and gawk which was new/shiny (although not /that/ new).

I believe both were available in Linux back then. I believe in the above anecdote both were consulted with the emphasis on AT&T-style awk for obvious reasons.