troff (1972) and eqn (1974) also existed. I don't know if they were influenced by PUB. SCRIPT (1968)[1] had macros but it's unclear whether they were present at the beginning or added later. RUNOFF (ancestor of troff) doesn't appear to have had macros. I've heard that Forth documentation was produced using a formatter written in Forth, that let the user switch between documet text and Forth code, but idk the dates or specific for this.
Anyway I'm sure PUB was influential but the idea of markup languages with macros certainly wasn't unique to it.
[1] https://en.wikipedia.org/wiki/SCRIPT_(markup)